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Volume 21, Issue 2April–June 2011

FEATURING:Ab initio No Core Shell Model • Microscopic Evolution

of Nuclear Equilibrium Shapes

Nuclear Physics NewsVolume 21/No. 2

Vol. 21, No. 2, 2011, Nuclear Physics News 1

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NuclearPhysics

News

2 Nuclear Physics News, Vol. 21, No. 2, 2011

Cover illustration: The Test Storage Ring TSR, presently at the Max-Planck-Institut für Kernphysik in Heidelberg-seearticle on page 33.

Volume 21/No. 2

Contents

Editorial .............................................................................................................................................................. 3Feature ArticleAb initio No Core Shell Model

by Bruce R. Barrett, Petr Navrátil, and James P. Vary................................................................................. 5Facilities and MethodsDirect Mass Measurements of Short-Lived Nuclides at the Storage Ring Facility in Lanzhou

by Yuri A. Litvinov and Hushan Xu ...............................................................................................................13The UNEDF Project

by Richard Furnstahl .....................................................................................................................................18Meeting Reports25th International Nuclear Physics Conference

by Jens Dilling ...............................................................................................................................................25Zakopane Conference on Nuclear Physics, “Extremes of the Nuclear Landscape”

by Bogdan Fornal ..........................................................................................................................................26The International Symposium on New Faces of Atomic Nuclei

by Takaharu Otsuka.......................................................................................................................................29Waltzing to the Nuclear Limits: A Symposium in Honor of Lee Riedinger

by Ani Aprahamian, Mike Carpenter, Rick Casten, Jolie Cizewski, Daryl Hartley, Filip Kondev, Witek Nazarewicz, and Mark Riley.........................................................................................30

News and views .................................................................................................................................................32Calendar ............................................................................................................................................................44

editorial


The views expressed here do not represent the views and policies of NuPECC except where explicitly identified.

Scholarpedia in Nuclear Physics

A recent development in our soci-ety is the access to information for thegreatest number of citizens. Websiteswhere we can find information on vir-tually all human activities multiplyevery day. However, it is known thatthe citizen must be exceedingly carefulconcerning information obtained onthe Web. The challenge today is notobtaining access to information but thequality of that information; we all wantinformation that we can trust.

Scholarpedia is an encyclopediaon the Web (http://www.Scholarpe-dia.org/) whose ambition is to offerencyclopedic articles of quality, withcertified information in many scien-tific fields. Scholarpedia at this time isnot a general encyclopedia; currentlyit focuses on the fields of computa-tional neuroscience, dynamical sys-tems, computational intelligence,physics and astrophysics, and in partic-ular for what we are concerned withhere, nuclear physics (http://www.Scholarpedia.org/article/Encyclopedia_of_Nuclear_Physics).

If quality of information is a pri-mary objective, the goal of Scholarpe-dia is even more ambitious—toprovide open-access encyclopedicpeer-reviewed articles written by rec-ognized experts elected by the publicor invited by Scholarpedia editors.The articles are maintained andevolved through similar mechanismsas Wikipedia. Among Scholarpediaauthors are 15 Nobel laureates, 4Fields medalists, and hundreds oforiginal inventors and discoverers.Thus Scholarpedia’s articles can be

cited in the same way as any otherpeer-reviewed article. In that senseScholarpedia has features commonlyassociated with open-access onlineacademic journals. Each article has a“curator”—typically its author—whois responsible for its content. Anymodification of the article must beapproved by the curator before itappears in the final, approved version.

What makes Scholarpedia uniqueis that each article’s content is theultimate responsibility of one of theleading experts on the topic. Theexpert acts as each article’s curator,vetting revisions that can be proposedby any verified user of Scholarpedia.The names of current curators areplaced at the top of each article, signi-fying their ongoing involvement withand responsibility for that article. Thename of the original author is given atthe bottom of each article, and perma-nently stored in the Scholarpediaarchive. Over time the leading role ofan article will shift to other scholars,ensuring that it remains timely, accu-rate, and relevant. The process ofcuratorship makes Scholarpedia aunique project. Ernest Rutherfordwrote the article “Radioactivity” forthe 11th edition of the EncyclopediaBritannica in 1910. If Britannica hadthe feature of curatorship, the bestexperts of today would be competingwith each other for the honor ofbecoming curator of Ernest Ruther-ford’s article. The goal of Scholarpe-dia is to identify and convince today’sErnest Rutherfords to write encyclo-pedic articles on their fundamental

discoveries, so that 100 years fromnow the best experts will be willing tomaintain and update these articles.Herein also lies the greatest differencebetween Scholarpedia and traditionalprint media: although the initialauthorship and review are similar to aprint journal, articles are not frozenand outdated, but dynamic, subject toan ongoing process of improvementmoderated by their curators. Thisallows Scholarpedia to be up-to-date,yet maintain the highest quality ofcontent. Upon approval, articles inScholarpedia are archived in a journalhttp://www.Scholarpedia.org/article/Special:Journal (ISSN 1941 6016) sothat they may be cited in the sameway as any other peer-reviewedarticle.

The citation, found below the arti-cle’s title, always refers to the latestapproved version of the article that isshown to visitors by default. Any par-ticular approved revision of the articlecan also be cited. Taking as an exam-ple an article by Prof. Alexandra Gadeand Prof. C. Konrad Gelbke The_NSCL_laboratory_and_the_FRIB_faci-lity, on the NSCL laboratory http://www.nscl.msu.edu and the FRIBfacility http://www.frib.msu.edu, itsdifferent versions after approval willform an historical witness of the evo-lution of the NSCL laboratory and inparticular of the evolution of theFRIB project. Written for the nuclearphysics section of Scholarpedia, it canbe sited as: Alexandra Gade and C.Konrad Gelbke (2010), Scholarpedia,5(1):9651.

editorial


When we were asked eighteenmonths ago to initiate the Scholarpe-dia section on nuclear physics weimmediately realized the importanceof the task both scientifically and interms of personal commitment.Given the challenges of our disci-pline we both agreed to commit our-selves to this project in order to helpto further popularize scientificachievements in nuclear physics andin its applications. The aim is to offerhigh-level scientific articles that canbe read and understood by the entirescientific community, science stu-dents, science journalists, and theeducated public but that may also beof interest to our colleagues. Toensure these requirements, the idealScholarpedia article is written in“Scientific American” or slightlymore advanced style, as appropriateat least for advanced undergraduatestudents in that area or graduate stu-dents in adjacent areas. The role ofthe encyclopedia in nuclear physicsis also to be involved in major scien-tific events, to inform journalists andput them in contact with the authorsof the relevant articles.

The work was initiated with thesupport of some close collaborators.Today in the nuclear physics sectionof Scholarpedia one can find articleseither accepted by the referees or stillin the referring process or articles thatare “scheduled,” that is, the authorshave accepted to write the article butthey have not yet submitted theirdraft. The quality of the already pub-lished articles and the enthusiasm ofthe first contributors strengthen ourdetermination to bring to a successfulconclusion this project. Of coursemuch remains to be done. For this ini-tiative to succeed, it needs all of us,all of our community to contributeand to popularize the project. This isthe ultimate meaning of this article,certainly to present the nuclear phys-ics section of Scholarpedia, todescribe its objectives, but also toencourage the whole of the nuclearphysics community to adopt this toolby making suggestions, proposals forauthors and to arrive—why not?—atwhat is the ultimate goal of Scholar-pedia, the authors of each articlebeing recognized by the entirecommunity.

NICOLAS ALAMANOS

Institut de Recherche sur les liosFondamentales de l’Univers (IRFU),

CEA Saclay, France

PAUL-HENRI HEENEN

Free University of Brussels, Belgium

feature article


Ab initio No Core Shell Model

BRUCE R. BARRETT Department of Physics, University of Arizona, Tucson, Arizona, USA

PETR NAVRÁTIL Theory Group, TRIUMF, Vancouver, Canada Physics Division, Lawrence Livermore National Laboratory, Livermore, California, USA1

JAMES P. VARY Department of Physics and Astronomy, Iowa State University, Ames, Iowa, USA

Introduction A long-standing goal of nuclear theory is to determine

the properties of atomic nuclei based on the fundamentalinteractions among the protons and neutrons (i.e., nucle-ons). By adopting nucleon-nucleon (NN), three-nucleon(NNN), and higher-nucleon interactions determined fromeither meson exchange theory or QCD, with couplingsfixed by few-body systems, we preserve the predictivepower of nuclear theory. This foundation enables tests ofnature’s fundamental symmetries and offers new vistas forthe full range of complex nuclear phenomena.

Basic questions that drive our quest for a microscopicpredictive theory of nuclear phenomena include:

1. What controls nuclear saturation? 2. How the nuclear shell model emerges from the underly-

ing theory? 3. What are the properties of nuclei with extreme neutron/

proton ratios? 4. Can we predict useful cross-sections that cannot be

measured? 5. Can nuclei provide precision tests of the fundamental

laws of nature? 6. Under what conditions do we need QCD to describe

nuclear structure?

among others. Along with other ab initio nuclear theory groups, we

have pursued these questions [1] with meson-theoreticalNN interactions, such as CD-Bonn [2] and Argonne V18[3], that were tuned to provide high-quality descriptions ofthe NN scattering phase shifts and deuteron properties. We

then add meson-theoretic NNN interactions such as theTucson-Melbourne [4] or Urbana IX [5] interactions.

More recently, we have adopted realistic NN and NNNinteractions with ties to QCD. Chiral perturbation theorywithin effective field theory (χEFT) [6] provides us with apromising bridge between QCD and hadronic systems [7].In this approach one works consistently with systems ofincreasing nucleon number [8–10] and makes use of theexplicit and spontaneous breaking of chiral symmetry toexpand the strong interaction in terms of a dimensionlessconstant, the ratio of a generic small momentum divided bythe chiral symmetry breaking scale taken to be about1GeV/c. The resulting NN and NNN interactions, characterizedby the order of the expansion retained (e.g., “next-to-next-to leading order” is NNLO) [11, 12], provide a high-qual-ity fit to the NN data and the A = 3 ground-state (g.s.)properties. The derivations of NN, NNN, and so on interac-tions within meson-exchange and χEFT are well

Figure 1. Schematic illustration on how Lee-Suzuki (LS)similarity transformation [14] yields an Heff in a finite modelspace P decoupled from the infinite complementary Q space. 1Present address.

feature article


established but are not subjects of this review. Our focus issolution of the non-relativistic quantum many-body Hamil-tonian that includes these interactions using our no coreshell model (NCSM) formalism. In the next section we willbriefly outline the NCSM formalism [1, 13] and thenpresent applications, results, and extensions in latersections.

The Ab Initio NCSM Formalism The ab initio NCSM employs realistic interactions, pre-

serves all their symmetries, and treats all A nucleonsequally in a basis space of Slater determinants using a sin-gle-particle basis, such as the 3D harmonic oscillator (HO)[1, 13]. From this foundation, we show how to derive thewell-known standard nuclear shell model, introduced byMaria Goeppert-Mayer and Hans D. Jensen in 1949 (NobelPrize in physics, 1963), that treats only a small number ofvalence nucleons outside of inert closed shells. In addition,we show that the ab initio NCSM combined with the Reso-nating Group Method (RGM) provides the foundation formicroscopic solutions of nuclear reactions with full predic-tive power.

In the ab initio NCSM, we start with the translationallyinvariant, intrinsic Hamiltonian for all A nucleons. Allterms act on relative coordinates—there are no single-par-ticle energies. We then add the HO center-of-mass (CM)Hamiltonian to provide a mean-field potential thatimproves convergence. The effects of the CM interactionare easily separated and later subtracted. Since realistic NN+ NNN interactions are strong at short distances we mustintroduce a theoretically sound renormalization procedureto render the problem solvable in a basis space with avail-able computer resources. We adopt a renormalization pro-cedure specified by a similarity transformation that softens

the interactions and generates effective operators for allobservables while preserving all experimental quantities inthe low-energy domain. The derived “effective” interac-tions still act among all A nucleons and preserve all thesymmetries of the initial or “bare” NN + NNN interactions.There are two such renormalization procedures that wecurrently employ, one called the Lee-Suzuki (LS) scheme[14] and the other called the Similarity RenormalizationGroup (SRG) [15].

Figure 2. Illustration of how the SRG procedure [15] weakens the strong off-diagonal couplings of an NN potential inmomentum space as the flow proceeds to smaller values of l (left to right panels).

2 4 6 8 10 12 14 16 18 20 22N

max

−29

−28

−27

−26

−25

−24

E [

MeV

]

bareSRG

4He

NN + NNN

chiral EFT

Figure 3. Convergence of the 4He g.s. energy with the sizeof the HO basis. Calculations with the bare (dashed line)and the SRG evolved (solid line) cEFT NN+NNNinteractions are compared. The SRG evolution parameterl= 2 fm-1 was used (Figure 2). The dotted line denotes theextrapolated g.s. energy (-28.5 MeV), which is close to theexperiment (-28.3 MeV).

feature article


For LS renormalization, the infinite HO basis space isdivided into a finite model space and an infinite excludedspace by the use of projection operators P and Q, respec-tively. Then the LS effective Hamiltonian Heff is obtainedby performing a similarity transformation, X, on the bareHamiltonian, H, and imposing the decoupling conditionQXHX−1P = 0; that is, Heff has no matrix elements betweenthe P and Q spaces, as shown schematically in Figure 1.Determination of the exact X requires the solution of thefull A-body problem, which is not feasible. However, thedetermination of the A-nucleon Heff from two-or three-body matrix elements, obtained by the solution of the two-or three-body cluster problem, results in an excellentapproximation. It also ensures that one recovers the origi-nal full problem, if the model space approaches the infinitespace, so that the approximation is fully controlled. The LSmethod can be applied to arbitrary modern NN (NN +NNN) potentials in either coordinate or momentum space.

Recently, we have also adopted the SRG approach [15]for softening the NN + NNN interactions. By varying aflow parameter, one can dial down the coupling betweenthe high-energy and low-energy parts of the NN (or NN +NNN) interaction, as illustrated in Figure 2. These SRGHamiltonians can be solved in any model space P, whichis now a simple truncation of the infinite basis SRGHamiltonian. Figure 3 shows such results for 4He as afunction of the P-space size given in terms of NmaxhΩ, themaximum HO energy of configurations included abovethe unperturbed g.s. configuration. The figure clearly

shows that the accelerated rate of convergence for thesofter SRG interactions over the bare NN (or NN + NNN)interaction.

NCSM Applications and Results The results of numerous ab initio NCSM applications not

only show good convergence with regard to increasing size ofthe model space P but also have been able to reproduceknown properties of 0p-shell nuclei as well as explain existingpuzzles and make predictions of, as yet, unexplained nuclearphenomenon. We list some illustrative examples here.

We display in Figure 4 the natural-parity excitationspectra of four nuclei in the middle of the 0p−shell withboth the NN and the NN + NNN effective interactionsfrom χEFT [16]. Overall, the NNN interaction contributessignificantly to improve theory in comparison with experi-ment. This is especially well-demonstrated in the odd massnuclei for the lowest, few excited states. The case of theg.s. spin of 10B and its sensitivity to the presence of theNNN interaction is clearly evident.

A recent calculation has determined the Gamow-Teller(GT) matrix element for the beta decay of 14C, including theeffect of NNN forces [17]. These investigations show thatthe very long lifetime for 14C arises from a cancellationbetween 0p-shell NN- and NNN-interaction contributions tothe GT matrix element, as shown in Figure 5. These 14Cresults were obtained in the largest basis space achieved todate with NNN interactions, Nmax = 8 (8hΩ) or approxi-mately one billion configurations.

0

4

8

NN+NNN Exp NN

3 + 3 +1 +

1 +

0 +; 10 +; 1

1 +

1 +

2 +

2 +

3 +

3 +

2 +; 1

2 +; 12 +

2 +

4 +

4 +

2 +; 1

2 +; 1

hΩ=14

0

4

8

12

16

NN+NNN Exp NN 3/2-

3/2-

1/2-

1/2-

5/2-

5/2-

3/2-

3/2-

7/2-

7/2-

5/2-

5/2-

5/2-

5/2-

1/2-; 3/2

1/2-; 3/2

0

4

8

12

16

NN+NNN Exp NN0 + 0 +

2 +

2 +

1 +

1 +4 +

4 +

1 +; 1 1 +; 1

2 +; 1 2 +; 1

0 +; 1

0 +; 1

0

4

8

12

16

NN+NNN Exp NN 1/2- 1/2-

3/2-

3/2-

5/2-

5/2-

1/2-

1/2-

3/2-

3/2-

7/2-

7/2-

3/2-; 3/2

3/2-; 3/2

10B11B 12C 13C

Figure 4. States dominated by 0p-shell configurations for 10B, 11B, 12C, and 13C calculated at Nmax = 6 using hΩ= 15MeV (14 MeV for 10B). Most of the eigenstates are isospin T = 0 or 1/2, the isospin label is explicitly shown only forstates with T = 1 or 3/2. The excitation energy scales are in MeV (adopted from Ref [16]).

feature article


Other noteworthy results include an explanation of thevery small quadrupole moment (Q) in 6Li due to a strongcancellation between the one-and two-body contributionsto Q [18] (Figure 6). Recent calculations for 12C explainedthe measured 12CB (M1) transition from the g.s. to the(1+, 1) state at 15.11 MeV and showed more than a factorof 2 enhancement arising from the NNN interaction. Neu-trino elastic and inelastic cross sections on 12C were shownto be similarly sensitive to the NNN interaction and theircontributions significantly improve agreement with experi-ment [19]. Working in collaboration with experimentalists,we uncovered a puzzle in the GT-excited state strengths in A= 14 nuclei [20]. Its resolution may lie in the role of intruder-state admixtures, but this will require further work.

Extensions of the NCSM for Treating Heavier Mass Nuclei

The basic idea of the ab initio Shell Model with a Core[21] is to use the well-established ab initio NCSM to solve

for the core and one-and two-body terms that are neededfor performing standard Shell Model (SSM) calculationsfor nuclei in the sd-and pf-shells. Such SSM calculationscan be performed in vastly smaller model spaces than thoserequired for converged NCSM calculations.

For illustration let us consider 0p-shell nuclei. We firstperform a standard ab initio NCSM calculation to obtainconverged eigenenergies and eigenfunctions for the A = 6system (e.g., 6Li). Next, we carry out a unitary transforma-tion of these 6Li results into the smaller model space of 0hΩexcitations, which is equivalent to a neutron and a proton inthe 0p-shell and the other four nucleons energetically frozenin the 0s-shell. Thus, we obtain only two-body matrix ele-ments in the 0p-shell, although we started with a full solu-tion of the A = 6 system in the NCSM approach. However,these two-body matrix elements contain all the physics ofthe six-nucleon system. These two-body matrix elementscan be separated into a core and one- and two-body compo-nents suitable for SSM calculations. In a similar manner wecan calculate the seven-body cluster in the 0p-shell by per-forming an ab initio NCSM calculation for 7Li and trans-forming this result into the 0p-shell. In this case, we can alsodetermine the three-body term in the 0p-shell. These coreand one-, two-, and three-body terms can then be used toperform SSM calculations for all the nuclei in the 0p-shell,in much smaller model spaces. Effects of neglected four-body interactions appear to be small.

-0.03

-0.02

-0.01

0

0.01

0.02

0.03

GT

mat

rix

elem

ent

no 3NF forceswith 3NF forces (c

D= -0.2)

with 3NF forces (cD

= -2.0)

s p sd pf sdg pfh sdgi pfhj sdgik pfhjl

shell

-0.1

0

0.1

0.2

0.3

0.2924

Figure 5. Contributions to the 14C beta decay matrix elementas a function of HO shell when the nuclear structure isdescribed by the cEFT interaction (adopted from Ref. [17]).Top panel displays the contributions with (two right bars ofeach triplet) and without (leftmost bar of each triplet) theNNN force at Nmax = 8. Contributions are summed withineach shell to yield a total for that shell. The bottom paneldisplays the running sum of the GT contributions over theshells. Note the order-of-magnitude suppression of the 0p-shell contributions arising from the NNN force.

0 2 4 6 8 10 12 14Nmax

0.3

0.2

0.1

0

0.1

0.2

0.3

Qe

fm2

6Li Q 1 1,T 0

1b

2b

1 2b

Qexp 0.08178 164 efm2

Figure 6. The quadrupole moment (Q) of the g.s. for 6Li

[1+(T = 0) is shown in terms of one- and two-body contri-butions, as a function of increasing model-space size. Theone- and two-body contributions and total Q are depicted aswhite, gray and black histograms, respectively [18].

feature article


The same approach, outlined previously for obtainingthe effective components of the shell-model Hamiltonianin a single major shell, for example, the 0p-shell, can alsobe utilized for computing the effective components of anyphysical operator in the same major shell. See Ref. [18]for details. The results of such calculations for the qua-drupole moment (Q) of 6Li are illustrated in Figure 6.Clearly, the very small Q-moment for 6Li arises fromcomplex many-body correlations among all six nucleons,leading to a large cancellation between the one-and two-body contributions.

The above 0p-shell results encourage us to extend thisapproach to nuclei in the sd-shell, which will require con-verged results for nuclei with A = 16, 17, 18, and 19. Inthis regard we are working on a new version of the Impor-tance Truncation approach of Roth [22] to obtain theseresults.

Applications to Nuclear Reactions A realistic ab initio description of light nuclei with pre-

dictive power must have the capability to describe allbound and unbound states within a unified framework. Abinitio calculations for scattering processes involving morethan four nucleons overall are challenging and still a rareexception [23]. Even calculations of resonant states arequite complicated [24]. The development of an ab initiotheory of low-energy nuclear reactions on light nuclei is

key to further refining our understanding of the fundamen-tal nuclear interactions among the constituent nucleons andproviding, at the same time, accurate predictions of crucialreaction rates for nuclear astrophysics.

A fully ab initio approach to nuclear reactions based onthe NCSM requires a more precise treatment of the wave-function asymptotics and the coupling to the continuum.Therefore, we have developed a new approach, the ab ini-tio NCSM/RGM [25, 26], capable of simultaneouslydescribing both bound and scattering states in light nuclei,by combining the resonating-group method (RGM) [27]with the ab initio NCSM. The RGM is a microscopic clus-ter technique based on the use of A-nucleon Hamiltonians,with fully anti-symmetric many-body wave functions builtassuming that the nucleons are grouped into clusters. Bycombining the NCSM with the RGM, we complement theability of the RGM to deal with scattering and reactionswith the utilization of realistic interactions and a consistentmicroscopic description of the nucleonic clusters achievedvia ab initio NCSM, while preserving important symme-tries, including the Pauli exclusion principle and transla-tional invariance.

Using the aforementioned NCSM/RGM formalism, weperformed extensive nucleon-4He calculations with theSRG-evolved NN potentials. The agreement of our calcu-lated n-4He and p-4He phase shifts with the experimentalones is quite reasonable for the S-wave, D-wave, and 2P1/2-wave. The 2P3/2 resonance is positioned at higher energy inthe calculation and the corresponding phase shifts areunderestimated with respect to the experimental results,although the disagreement becomes less and less pro-nounced beyond the resonance energy. The observed

-1

-0.5

0

0.5

1

Ay(θ

c.m

.)

NCSM/RGM Hardekopfet al. 1977

0 30 60 90 120 150θ

c.m. [deg]

0

100

200

300

dσ/d

Ω(θ

c.m

.) [m

b/sr

] Dodder et al. 1977Schwandt et al. 1971

0 30 60 90 120 150 180θ

c.m. [deg]

NCSM/RGM (14 MeV)Brokman 1957

Ep = 17 MeV

Ep ~ 12 MeV E

p ~ 17 MeV

Ep ~ 12 MeV

Ep = 14.32 MeV4

He(p,p)4He

Figure 7. Calculated p-4He differential cross section(bottom panels) and analyzing power (top panels) forproton laboratory energies Ep = 12, 14.32 and 17 MeVcompared to experimental data from Refs. [29, 30, 31, 32].The SRG-N3LO NN potential with l= 2.02 fm-1 was used.

0 1 2 3 4 5 6 7Ekin [MeV]

0

0.05

0.1

0.15

0.2

0.25

σ [b

]

7Be (p, p’) 7Be(1/2-)1+

1+3+ 2+

2+

0+

000100101Ekin [keV]

0

5

10

15

20

S-fa

ctor

[MeV

b]

Al01Al01Sch89Co05Kr87NCSM/RGM

d+3He → p+4He

Figure 8. Calculated inelastic 7Be(p,p¢)7Be(1/2−) crosssection with indicated positions of the P-wave resonances

(left). Calculated S-factor of the 3He(d,p)4He fusionreaction compared to experimental data (right). Energies

are in the center of mass. The SRG-N3LO NN potential

with l = 1.85 fm−1 (l = 1.5 fm−1) was used, respectively.

feature article


difference is largely due to a reduction in spin-orbitstrength caused by the neglect of the NNN interaction inour calculations. More details are given in Ref. [28]. Forenergies beyond the 2P3/2 resonance, our calculations com-pare favorably with the experimental data. This is shown inFigure 7, where the NCSM/RGM p−4He results are com-pared to various experimental data sets [29–32] in theenergy range Ep ~ 12−17 MeV.

The 7Be(p,γ)8B capture reaction plays a very impor-tant role in nuclear astrophysics as it serves as an inputfor understanding the solar neutrino flux [33]. Theextrapolation of the S-factor (i.e., the cross-sectiondivided by the Gamow factor) to astrophysically relevantenergies relies on nuclear theory. We performed NCSM/RGM calculations of the p-7Be scattering as a necessarypreparatory step to investigate the 7Be(p,γ)8B capturereaction [28]. In the calculation presented in Figure 8 thatincluded the g.s. and the lowest four excited states of 7Bewe found a 2+ state bound by 0.16 MeV corresponding tothe 8B ground state. In experiment, 8B is bound by 137keV [34]. The calculated lowest 1+ resonance appears atabout 0.7 MeV. It corresponds to the experimental 8B 1+

state at Ex = 0.77 MeV. This resonance dominates theinelastic cross-section as seen in the left part of Figure 8.We find a 0+, another 1+, and two 2+ resonances notincluded in the current 8B evaluation [34]. We note, how-ever, that in the very recent Ref. [35], the authors claimthe observation of low-lying 0+ and 2+ resonances, basedon an R-matrix analysis of their p-7Be scattering experi-ment. Effects of the 0+, the second 1+, and the second 2+

states are visible in the inelastic cross-section above thefirst 1+ state resonance. On the other hand, the 3+ reso-nance affects, in particular, the elastic cross section. Cal-culations of the 7Be(p,γ)8B capture within the NCSM/RGM are in progress.

The deuterium-tritium reaction is important for possi-ble future fusion energy generation. Even though it hasbeen well studied experimentally, its first principlestheoretical understanding is important. The 3H(d,n)4He andits mirror reaction 3He(d,p)4He are also of interest forunderstanding primordial nucleosynthesis. In addition, the3He(d,p)4He is one of the few reactions to present strongelectron screening effects. The first ab initio calculationsfor these reactions within the NCSM/RGM framework areunderway. Our first results were obtained with the SRGNN interaction with λ = 1.5 fm−1, for which the resonanceenergies are close to experimental values [36]. The astro-physical S-factor for the 3He(d,p)4He reaction from beam-

target experiments is compared to NCSM/RGM calcula-tions for bare nuclei in the right panel of Figure 8. Weobserve a slightly different shape of the peak than that sug-gested by the “Trojan-horse” data from Ref. [37]. Also, nolow-energy enhancement is present in the theoreticalresults contrary to the beam-target data of Ref. [38]affected by the electron screening.

Summary and Outlook The ab initio NCSM treats all A nucleons equally with

modern NN + NNN interactions and successfully describesproperties of nuclei throughout the 0p-shell. In combina-tion with the RGM, it provides a truly microscopicapproach for nuclear reactions. Several investigations areunderway to extend the ab initio NCSM to nuclei with A >16 and to more completely unify the original ab initioNCSM with the NCSM/RGM approach. The outlookincludes, but is not limited to:

1. Development of effective NN, NNN, and even NNNNinteractions for more detailed investigations of 0p-andsd-shell nuclei.

2. Development of symmetry-adapted basis spaces suchas SU(3) [39].

3. Extension of the NCSM calculations to sd-and pf-shellnuclei (i.e., ab initio SM with a core).

4. Extension of the NCSM/RGM approach to nuclearreactions with more massive projectiles and three-clus-ter final states

5. Coupling of the binary-cluster (A−a,a) NCSM/RGMbasis and the standard A-nucleon NCSM basis to unifythe original ab initio NCSM and NCSM/RGMapproaches. This will result in an optimal and balanceddescription of both bound and unbound states. Wename this approach ab initio NCSM with the contin-uum (NCSMC).

6. Improved extrapolation techniques for estimating con-verged results.

7. The development of new techniques for quantifyingtheoretical uncertainties.

Acknowledgments BRB acknowledges partial support of this work by the

NSF under grants PHY-0555396 and PHY0854912 and JPVacknowledges partial support from DE-FG02-87ER40371and DE-FC02-09ER41582 (SciDAC/UNEDF). Prepared inpart by LLNL under Contract DE-AC52-07NA27344.PN acknowledges support from the NSERC Grant No.

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401945-2011, and LLNL LDRD Grant No. PLS-09-ERD-020, and from the LLNL Institutional Computing GrandChallenge Program.

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JAMES VARY

PETR NAVRÁTIL

BRUCE R. BARRETT

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facilities and methods


Direct Mass Measurements of Short-Lived Nuclides at the Storage Ring Facility in Lanzhou

Introduction Properties of unstable nuclei are

indispensable for our understandingof nuclear structure and of nucleosyn-thesis processes in stars. Today, accu-rate data for nuclides lying far fromthe valley of beta-stability arerequired. However, these nuclides cangenerally be characterized by shorthalf-lives and very small productionrates, which makes their experimentalinvestigation extremely difficult.Very fast and efficient methods aretherefore needed.

The recent advent of experimentaltechniques based on projectile frag-mentation, in-flight separation, andheavy-ion storage rings has enabledexperiments with stored exotic nucleiat relativistic energies [1, 2]. Suchmeasurements have proven to be very

efficient. For instance, a single storednucleus is often sufficient for thedetermination of its mass [3]. Also, anumber of new isotopes have beendiscovered and their masses and life-times have been determined [4, 5].Thus, experiments on nuclides withsmallest production rates are feasible.

Storage Ring Facility in Lanzhou Presently there are two storage

ring facilities worldwide performingsuch experiments [6]. The first one isin operation for about two decades atthe Helmholtz Centre for Heavy IonResearch GSI in Darmstadt, where theexotic nuclei are produced in projec-tile fragmentation or fission of pri-mary beams accelerated by the heavy-ion synchrotron SIS. The fragments

are then separated in flight with theprojectile fragment separator FRS andare injected into the experimentalstorage ring ESR, where their proper-ties are investigated [1, 2].

The second storage ring facilityfor nuclear physics research, CoolerStorage Ring at the Heavy IonResearch Facility in Lanzhou(HIRFL-CSR), has been recentlytaken into operation at the Institute ofModern Physics, Chinese Academy ofSciences in Lanzhou (China) [7]. Thelaboratory portrait of the HIRFL-CSRfacility has been presented in NuclearPhysics News in 2007 [8]. The layoutof the facility is schematically illus-trated in Figure 1. Its principle is verysimilar to the GSI facility. Here, theexperimental cooler-storage ringCSRe is coupled to the heavy-ion

Figure 1. Schematic view of the high-energy part of the HIRFL-CSR facilityin Lanzhou [7,8].

Figure 2. Photo of the experimental cooler-storage ring CSRe in Lanzhou [7,8](Photo: IMP, Lanzhou, China).



synchrotron (main cooler-storagering) CSRm via the in-flight fragmentseparator RIBLL2.

Exotic nuclei are produced byfragmenting relativistic primarybeams accelerated by the CSRm in aproduction target located at theentrance of the RIBLL2. The nuclidesof interest are separated in flight withRIBLL2 and are injected and stored inthe CSRe. A photo of the CSRe isshown in Figure 2.

Isochronous Mass Spectrometry The revolution times, T, or the revo-

lution frequencies, f, of various storedions are related (in first order) to theirmass-to-charge ratios, m/q, via [1]:

where γ is the relativistic Lorentz fac-tor, γt the transition point of the stor-age ring, and Δv/v denotes thevelocity spread of the stored ions.This is the central formula for storagering experiments. It is clear that

different nuclear species can beresolved in the ring by their revolu-tion frequencies (revolution times), ifthe second term on the right-hand sidecontaining Δv/v vanishes or becomesnegligibly small. However, the sec-ondary beams inevitably have Δv/v ofthe order of a few percent due to theirproduction in a nuclear reaction.

Two complementary ways exist tominimize this term. The first one relieson the reduction of the velocity spreadby stochastic and/or electron coolingand is the basis of the Schottky massspectrometry (SMS) [9]. The secondway is to tune the ring into a special iso-chronous ion-optical mode and to injectthe ions at energies corresponding to γ =γt [10]. In this case the velocity spread iscompensated by the orbit lengths of theions, i.e. the frequencies of the storedions become independent of their veloc-ity spread. This is the basis of isochro-nous mass spectrometry (IMS). Thebiggest advantage of the IMS is that itdoes not require beam cooling and is aunique technique for mass measure-ments of very short-lived nuclei [11].Here we report on the recent mass mea-surements conducted at CSRe. So faronly the IMS method has beenemployed. Experiments with cooledions applying the SMS method areplanned in near future.

The transition point of the CSRe isγt = 1.395. The fragments emergingthe target at this energy are highly-ionized. For the case of nuclidesaddressed so far at the CSRe (Z ≤ 36),one can safely assume that they weremostly stored as bare nuclei.

The revolution times were mea-sured with a dedicated Time-of-Flight(ToF) detector [12]. The detector con-tains a 19 μg/cm2 thick, 40 mm indiameter carbon foil, which is insertedinto the CSRe aperture. Each storedion penetrates the foil at every revolu-tion which causes the release of sec-ondary electrons from the foil surface.The electrons are guided isochronously

by perpendicularly arranged electro-static and magnetic fields to a set ofmicro-channel plates. The signalsfrom the ToF detector are directlysampled with a fast digital oscillo-scope. The recording time is typically200 μs for each injection which corre-sponds to about 320 revolutions of theions in the CSRe.

First Mass Measurements at CSRe Pilot mass measurements have

been conducted in December 2007. Inthat experiment, N = Z fragmentswere produced in fragmentation of36Ar primary beams [13, 14]. Themasses of 34Cl and 30P have beendetermined with a relative mass accu-racy δm/m ≈ 8•10–6 in excellent agre-ement with tabulated values from theAtomic-Mass Evaluation AME [15].Though the achieved mass accuracywas rather poor, the isochronous ion-optical mode of the CSRe, the detec-tion and data acquisition systems aswell as data analysis methods havebeen successfully tested.

D D

g

D g

g

D

( )T

T

f

f

m/q

m/q

v

v= − = − −

⎛⎝⎜

⎞⎠⎟

11

2

2

2t t

( ),

Figure 3. A part of the measuredrevolution time spectrum of A = 2Z-1nuclei stored in the CSRe. Nuclideswhose masses were measured directlyfor the first time are indicated withbold symbols [18].

Figure 4. Regions in the temperature-density plane where 64Ge is a waitingpoint (WP) with an effective lifetimelonger than 50% of the b-decay lifetime.Shaded areas were deduced assumingone sigma uncertainties of the AME(gray) and the new (black) mass valuesfor 65As. The figure is from Ref. [18].



Following the first successful mea-surements, an attempt to access so farunknown masses has been undertaken[16]. Neutron-deficient A = 2Z−1nuclei have been produced by frag-menting the enriched 78Kr primarybeams. Masses of three short-livednuclides were obtained for the firsttime, namely for 63Ge (T1/2 = 97(22)ms), 65As (T1/2 = 128(16) ms), and67Se (T1/2 = 136(12) ms) [17]. Thecounting statistics was very limitedand only a moderate mass accuracywas achieved. For instance the massexcess value of 65As was ME(65As) =−47428(±530) keV. It has been real-ized that the resolving power of theCSRe mass spectrometry is mainlylimited by long-term instabilities ofthe guiding magnetic fields, whichcause revolution-time drifts of theentire spectrum for different injec-tions into the CSRe.

The experiment on A = 2Z−1 nucleiwas repeated in 2009 [18]. In a two-weeks run the data for about 700,000stored ions have been acquired. A part

of the measured time-of-flight spectrumis shown in Figure 3. The revolutiontime difference to a selected referencenuclide has been considered instead ofanalyzing the absolute revolution timesof the ions. By doing so, the effects dueto the instabilities were to a large extendcompensated and a resolving power ofabout 170,000 has been achieved. Byemploying the new analysis method, themasses for 63Ge, 65As, 67Se, and 71Kr(T1/2 = 100(3) ms) [17] nuclides havebeen determined with a relative massuncertainty of δm/m ≈ 2•10–6. Thesefour nuclides are indicated with boldsymbols in Figure 3. It is important tonote that only 309, 49, 104, and 28 par-ticles, respectively, were accumulatedfor these four nuclides, which provesthe high efficiency of the IMS measure-ments at the CSRe.

The achieved high mass accuracyfor the new masses is sufficient toconsider them in nuclear structure andastrophysics applications. One of suchapplications is the astrophysical rp-process, a sequence of proton captures

and β+ decays proceeding near theproton drip line, which is believed topower energetic X-ray bursts [19].The time of the rp-process and thusthe duration of the X-ray burst ismainly determined by the waitingpoint (WP) nuclei [20]. The latter arethe nuclei where the proton capturestalls and the rp-process has to pro-ceed via the slow β+ decay. One ofthe suggested WP nuclei is 64Ge. Todetermine the extend to which 64Ge isa waiting point, the knowledge of theproton separation energy of 65As,Sp(

65As), is required. Sp energies can be obtained by

computing the Coulomb displacementenergies (CDE) [21]. By using the newdata, the Spvalues for 63Ge, 65As, 67Se,and 71Kr nuclides could be determined[18]. The Sp energies for 63Ge, 65As,and 67Se agree well with the corre-sponding CDE calculations. However,for the case of 71Kr a 1.7σ discrepancyhas been observed, which may point tothe necessity to consider the deforma-tion and shape-coexistence effects,present in this mass region, in futureCDE calculations [18].

The obtained Sp(65As) = –90(85)

keV confirmed for the first timeexperimentally that 65As is unboundagainst proton emission at a 68.3%confidence level. The proton decayenergy is so low that a direct protonemission from the ground state of65As should be very weak due to theCoulomb barrier. We note, that theSp(

65As) agrees with the limit of Sp>-250 keV [22] based on the observedβ-decay and theoretical estimates ofthe proton penetrability.

Using the new Sp(65As) value, the

degree to which 64Ge is an rp-processWP nucleus can be determined.Figure 4 shows regions in the temper-ature-density plane where proton cap-tures reduce the effective lifetime of64Ge to less than 50% of the β-decaylifetime, thus resulting in a less effec-tive waiting point (no WP). The

Figure 5. Mass measurements conducted at the CSRe. Only nuclides withmeasured masses are shown. Employed primary beams are indicated with stars.GSI data are from Ref. [24].



temperatures and densities needed tobypass the 64Ge waiting point are nowrather well defined. Furthermore, ithas been shown in Ref. [18] that in theframework of a one-zone X-ray burstmodel [20] the 2σ variation of thenew Sp(

65As) value yields essentiallyidentical light curves. Calculationsshowed that 89–90% of the reactionflow passes 64Ge via proton captureindicating that 64Ge is not a signifi-cant rp-process waiting point. In con-trast, using the estimated Sp(

65As)from the AME, leads to a reduction ofthe proton capture flow to 54%.

Recent Measurements and Future Developments

The successful mass measure-ments program has been continued in2011. Masses of eight short-lived A =2Z−2 nuclides have been measuredfor the first time. These nuclides are43V (T1/2 = 80# ms), 46Mn (T1/2 =36.2(4) ms), 47Mn (T1/2 = 100(50) ms),49Fe (T1/2 = 64.7(3) ms), 52Co (T1/2 =115(23) ms), 53Ni (T1/2 = 45(15) ms),55Cu (T1/2 = 40# ms), and 56Cu (T1/2 >200# ms) [17], where “#” denotes esti-mated T1/2 values. The harvest of theCSRe mass measurements is illustratedon the chart of nuclides in Figure 5.

By employing a collimation ofsecondary beams at the FRS, a massresolving power of about 200,000 hasbeen achieved in IMS experiments atthe ESR [23]. However, the transmis-sion of exotic nuclei to the ESR wasdramatically reduced. Owing to thenew analysis method and to the high-rate capable ToF detector, a similarresolving power could be achieved atthe CSRe without limiting the trans-mission. This is an obvious advantageif more rare nuclides will beaddressed in future measurements.

A wide range of Δ(m/q)/(m/q) ≈ 13%can be covered simultaneously in oneion-optical setting of CSRe. However,the isochronous conditions are strictlyfulfilled only in a small m/q-range [23]

and only small “isochronous” parts ofrevolution time spectra have been ana-lyzed so far. The same effect has beenobserved also in the ESR experiments[23]. It is planned to install two time-of-flight detectors in one of the straightsections of the CSRe (Figure 1). Thiswill enable in-ring measurements ofvelocities of individual stored ions. Thisadditional information can be used tocorrect for the non-isochronous effectsand to maintain the high resolvingpower over the entire spectrum.

In conclusion, the first mass mea-surements at the CSRe have deliveredprecision data on short-lived neutron-deficient nuclides. A measurement of arevolution time requires a few ten revo-lutions of the ion in the ring, that isnuclei with half-lives as short as a fewten microseconds can be studied. Fur-thermore, only a few ten particles aresufficient to determine the mass with arelative mass accuracy of a few 10–6.Thus, the IMS at CSRe is an extremelyfast and a very efficient method.

Acknowledgments This article is entirely based on the

common effort of our colleagues withinthe broad international collaboration.To all of them we are deeply obliged.

References 1. B. Franzke, H. Geissel, and G. Münzen-

berg, Mass Spectrom. Rev. 27 (2008) 428. 2. Yu. A. Litvinov and F. Bosch, Rep.

Prog. Phys. 74 (2011) 016301. 3. L. Chen et al., Phys. Rev. Lett. 102

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YURI A. LITVINOV

GSI Helmholtzzentrum fürSchwerionenforschung, Darmstadt,

GermanyMax-Planck-Institut für Kernphysik,

Heidelberg, GermanyInstitute of Modern Physics, ChineseAcademy of Sciences, Lanzhou, China

HUSHAN XU

Institute of Modern Physics,Chinese Academy of Sciences,

Lanzhou, China



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17. National Nuclear Data Center, http://www.nndc.bnl.gov/

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The UNEDF Project

Overview A new era has dawned for nuclear

structure and reaction theory.Renewed interest in the physics ofnuclei is fueled by experiments at rareisotope beam facilities, which explorenew regions of exotic nuclei; by astro-physical observations and simula-tions, which require controlled extra-polations of the nuclear equation ofstate; by the use of nuclei in experi-ments on fundamental symmetries,which rely on robust nuclear structureinformation; and by nuclear energyand security needs, which include pre-dictions of reaction cross-sections andfission fragment properties. TheUNEDF collaboration of nuclear the-orists, applied mathematicians, and

computer scientists is addressing thisbroad spectrum of physics through acomprehensive study of all nuclei,based on the most accurate knowl-edge of the strong nuclear interaction,the most reliable theoreticalapproaches, the most advanced algo-rithms, and extensive computationalresources.

UNEDF stands for “UniversalNuclear Energy Density Functional.”The mission of this five-yearSciDAC (“Scientific Discovery thro-ugh Advanced Computing”) project isthree-fold [1]:

• First, to find an optimal energydensity functional (EDF) using allour knowledge of the nucleonic

Hamiltonian and basic nuclearproperties.

• Second, to apply the EDF theoryand its extensions to validate thefunctional using all the availablerelevant nuclear structure andreaction data.

• Third, to apply the validated the-ory to properties of interest thatcannot be measured, in particularthe properties needed for reactiontheory.

The long-term vision is to arrive at acomprehensive and quantitativedescription of nuclei and their reac-tions. UNEDF is striving to replacephenomenological models with awell-founded microscopic theory thatdelivers maximum predictive powerwith quantified uncertainties.

By nuclear theory standards,UNEDF is large: it involves over 50researchers from 9 universities and 7national laboratories. Annually, itprovides training to about 30 youngresearchers (postdocs and students).UNEDF is like a large experimentalcollaboration with multiple facets toits research goals.

The SciDAC model (http://www.scidac.gov) has led UNEDF membersto form partnerships in which appliedmathematicians and computer scien-tists work collaboratively with physi-cists to develop the required advancedalgorithms and tools. At the same time,the project has catalyzed new cross-cutting physics collaborations, whichinclude nuclear theorists around theworld as international partners. Thescope of the UNEDF project is large.Here we present brief snapshots thathighlight the collaborative effort,the progress made, and the future

Figure 1. Table of the nuclides and the scope of theoretical methods todescribe it.



prospects; more details and referencescan be found at the unedf.org website.

Forging New Connections The playing field for UNEDF is

the nuclear landscape of Figure 1. Thesizable area marked “terra incognita,”which is populated by unstable iso-topes with large neutron fractions, isof particular interest. Above the tableof nuclides are shown three broadclasses of theoretical methods, whichare also used in atomic and condensedmatter physics. The bulk of thenuclides are covered by Density Fun-ctional Theory (DFT), which provides

the theoretical underpinning and com-putational framework for building anuclear EDF. By enhancing andexploiting the overlaps with ab initioand configuration interaction (CI)approaches, we are constructing andvalidating a universal EDF informedby microscopic interactions as well asexperimental data.

The UNEDF components andpaths between them are shown in theUNEDF strategy diagram in Figure 2.New interconnections and collabora-tive efforts within and across theboundaries have become indispensi-ble. By necessity the developmentshave largely occurred in parallel; in

subsequent sections we give examplesof the interplay as UNEDF hasworked to fulfill its mission.

Enhancing ab initio Structure Calculations

Direct connections of the EDF tomicroscopic nuclear interactionsrequire improving the scope and accu-racy of ab initio methods. Majoradvances in ab initio nuclear structurecalculations under UNEDF havefocused on improving the effectiveuse of high performance computing—especially the efficient scaling to verylarge numbers of parallel processors.

A prime example of UNEDF syn-ergy has been the development of theAsynchronous Dynamic Load Bal-ancing (ADLB) software library byusing Green’s Function Monte Carlo(GFMC) calculations as a test bed.Load balancing means ensuring thatevery parallel processor is used effec-tively; it is essential to optimal scal-ing. The ADLB library has enabledGFMC to run efficiently on over100,000 core processors [2].

A major test case is the 12C energyand proton density (see Figure 3),which is also a proof of principlewhether a microscopic nuclear Hamil-tonian calibrated to few-body nucleican successfully predict the energy

Figure 3. Carbon-12 density calculatedwith GFMC using the ADLB library [2].

Figure 2. UNEDF project scope and various active interconnections.



and density distribution of largernuclei. Unlike quantum chemistry,where the Coulomb interaction isfirmly established, the input nuclearHamiltonian must be tested and imp-roved as needed even as the nuclearDFT itself is developed. The GFMC/ADLB combination predicts the 12Cexperimental energy and radius towithin 1%, which is a compelling val-idation [2]. The next targets areexcited states in 12C, including thefamous Hoyle state.

Configuration interaction ab ini-tio methods use basis expansions andrequire the (partial) diagonalization ofextremely large matrices. These areknown by various names according todetails of the implementation, includ-ing No-Core Shell Model (NCSM)and No-Core Full Configuration(NCFC) methods (see accompanyingarticle by Barrett, Navratil, and Vary).Improvements by applied mathemati-cians working with nuclear theoristson eigensolvers, data structures, andnew combinatorial algorithms haveresulted in substantial performancegains for CI codes such as MFDn,allowing efficient scaling to largenumbers of processors [3].

An example of what this scalingenables is the recent prediction of the 14Fmass and excitation spectrum in advanceof the experimental measurements,which meant solving a Hamiltonian

matrix of dimension 2 billion using30,000 cores [4] (Figure 4). The pre-dictions and measurement agreewithin the combined experimentaland theoretical uncertainties (notshown). Another recent applicationinvolving many UNEDF members isan explanation of the anomalouslylong lifetime of 14C by identifying thecritical role of the three-nucleon(NNN) force in its beta decay [5]. Wecan look forward to many such con-frontations of theory and experimen-tal data from rare isotope facilities.

CI codes used within the UNEDFproject apply both fully microscopicand phenomenological shell modelapproaches, and use different algo-rithms. But common computationalissues are leading UNEDF scientists todevelop the Leadership Class Configu-ration Interaction (LCCI) frameworkto unify, preserve, and disseminatevaluable CI codes and resources. Thiswill provide a user-friendly environ-ment for researchers to download andrun state-of-the-art CI codes neededfor theoretical predictions as well asexperimental analysis.

To make ab initio methods moreconvergent, it can be advantageousto “soften” the initial Hamiltonian bydecoupling low-momentum andhigh-momentum parts. Renormaliza-tion group (RG) methods achievethis decoupling by evolving interac-tions in small steps. The resultingtwo-nucleon (NN) potentials are veryconvergent but the initial NNN inter-action is also changed. Until recentlya consistent NNN evolution had notbeen achieved. But a UNEDF collab-oration successfully combined Simi-larity RG (SRG) evolution methodswith NCSM technology. Figure 5illustrates the improved convergencewith the evolved three-body force[7]. These SRG interactions are now

being applied to larger nuclei and inreaction calculations.

The interactions used in the 14Ccalculations and the SRG evolutionsare systematically constructed (out-side of UNEDF) using chiral effectivefield theory (EFT). UNEDF membershave demonstrated that the coupled-cluster (CC) ab initio method can beused to accurately calculate closed-shell medium-mass nuclei such as40,48C with chiral EFT two-body inter-actions (or RG-softened versions) aswell as proton halo nuclei like 19F [8].The CC formalism has been extended toinclude NNN forces and their inclusionin calculations of the heavier nuclei willbreak new barriers. A recent develop-ment is the first in-medium SRG diago-nalization of closed-shell nuclei such as40C with accuracy comparable to CCresults [9].

Microscopic Inputs to a Nuclear EDF

As implied by the diagram inFigure 2, multiple inputs and con-straints are being used to build a uni-versal nuclear EDF. The foundation is

Figure 5. Improved convergence inhelium-4 using Similarity Renorm-alization Group (SRG) interactions,including an evolved NNN force [7].

Figure 4. Theoretical (“ab-initio”)spectrum from NCFC compared toexperimental results for 14F [6].



provided by EDF’s of the Skyrmetype, whose phenomenological suc-cesses have been extensively bench-marked as part of the UNEDF project.Ab initio approaches can provide“control-data” to constrain more gen-eral functionals as well as to directlymotivate novel density and momen-tum dependences.

Ab initio calculations can be usedto test candidate EDF’s even for sys-tems not available in the laboratory.Current functionals are least con-strained in their isovector depen-dence, so a system of neutron dropswould be ideal, but the neutronswould not be self-bound. However,DFT says that the functional shouldwork with a theoretical externalpotential, which can be used to “trap”neutrons and adjust their density pro-files. UNEDF calculations applyingGFMC (up to 16 neutrons) and Auxil-iary Field Diffusion Monte Carlo(AFDMC, up to 54 neutrons) methodsto generate such control-data arebeing used to probe deficiencies ofconventional EDF parameterizationsand to improve them. In Figure 6 sucha comparison for radii is shown forthe original SLy4 functional and anadjusted version [10]. The neutrondrop results are validated by also

calculating with NCFC and with otherHamiltonians.

A parallel effort uses trapped neu-tron systems as well, but tests ab ini-tio DFT methods against fullcalculations based on the sameHamiltonian. A hybrid approach useschiral EFT for the long-distance (pionrange) NN and NNN interactions thatcan be translated into novel densitydependences through a revitalizedincarnation of the density matrixexpansion. These new functionals arebeing optimized and tested using theextensively developed EDF infra-structure [11].

Enhancing and Extending DFT Infrastructure

Much effort in the UNEDF projecthas been devoted to developing andimproving the algorithmic and com-putational infrastructure needed tooptimize candidate EDF’s and toapply symmetry restoration requiredfor accurate calculations of self-bound nuclei. Performance optimiza-tion of DFT-solver codes has enabledlarge-scale mass table calculations on9,060 processors for 840,000 configu-rations in 9,000 nuclei in a 12-hourrun. The MADNESS (MultiresolutionADaptive NumErical Scientific Simu-lation) framework is an example ofapplying state-of-the-art appliedmathematics technology to create aDFT solver with an adaptive pseudo-spectral method [12].

Another example is the optimiza-tion algorithm POUNDerS, developedby a UNEDF team of applied mathe-maticians, which yields dramaticcomputational savings over alterna-tive optimization methods, as seen inFigure 7. Using the UNEDF Experi-mental Database and the optimizedsolver HFBTHO, the Skyrme SLy4functional was re-optimized using the

derivative-free POUNDerS algorithm.The resulting parameterizationUNEDF0 sets a solid baseline ofnuclear ground-state properties tocompare with future functionals [13].New hybrid functionals with micro-scopic input from chiral EFT [11] arebeing optimized using this approach.

A New Era for Reaction Theory One of the principal aims of the

UNEDF project is to calculate reliablereaction cross-sections for astrophys-ics, nuclear energy, and national secu-rity, for which extensions of standardphenomenology is insufficient. Theinterplay of structure and reactions isessential for a successful descriptionof exotic nuclei as well. Such inter-play is characteristic of the ab initiono-core shell model/resonating-groupmethod (NCSM/RGM), which treatsbound and scattering states within aunified framework using fundamen-tal interactions between all nucleons.A quantitative proof-of-principle cal-culation of this approach is shown inFigure 8 [14]. A wide range of appli-cations is now possible including3H(d,n)4He fusion, the 7Be(p,γ)8Breaction important for solar neutrinophysics, and many more to come.

Figure 7. Greatly improved converg-ence is seen with the novel optimi-zation algorithm POUNDerS [13].

Figure 6. GFMC calculations of theradii of N neutrons in harmonicoscillator (HO) and Woods-Saxon (WS)traps, which are used to adjust the SLy4Skyrme functional [10].



Neutron reactions on heaviernuclei are being modeled using DFTresults to predict not just bound states,but also scattering states for nucleons.Microscopic calculations of reactioncross-sections for nucleon-nucleusscattering have been performed bycoupling the elastic channel to all par-ticle-hole excitations in the target,and also with one-nucleon pickupchannels. Target excitations were des-cribed in a random-phase (QRPA)framework using a Skyrme func-tional and the resulting transitionpotentials were used in large coupled-channel calculations. As illustrated inFigure 9, the calculated reactioncross-sections agree very well withexperimental data, and also with pre-dictions of global optical potentialswhere data are not available. For thefirst time, the observed absorption inthe reaction cross-section can beaccounted for by explicit channel cou-pling [15].

Another important capability forreactions is the calculation of leveldensities. A new proton-neutron algo-rithm for the parallel JMoments codewas recently designed and imple-mented, which improved its scalabil-

ity to tens of thousands of cores, andincreased its overall performance by afactor of more than 10,000. Thisdevelopment opens the door to calcu-lating accurate nuclear level densitiesand reaction rates for a large class ofnuclei [16].

Cold Atoms as a Testing Ground UNEDF theorists have made

important contributions to the studyof strongly coupled superfluid sys-tems such as ultracold Fermi atoms,which show many similarities to thecold nuclear matter found in the crustof neutron stars. Cold atoms makeexcellent laboratories for testing andimproving the computational methodsto be used for nuclei; indeed, GFMCand AFDMC calculations fromUNEDF scientists have set the stan-dard for numerical results of the uni-tary gas at zero temperature.

Cold atom systems allow predictionsof superfluid DFT that are testableagainst experiment. An example isshown in Figure 10, where a nuclearDFT code adapted to the antisymmetricsuperfluid local density approximation(ASLDA) [17] is applied to stronglyinteracting spin-imbalanced atomicgases in extremely elongated traps. Fam-ilies of Larkin-Ovchinnikov (LO) stateswith prominent transversal oscillationsof the pairing potential are predicted, asindicated by the radial alignment ofnodes, coexisting with a superfluid statehaving a smooth pairing potential [18].

A recent major UNEDF achieve-ment is the full implementation of thetime-dependent superfluid local den-sity approximation (TDSLDA) on a3D spatial lattice [16]. Unlike manypast approaches, matrix operations arenot needed and the size of the basisset it can handle is 2–3 orders of mag-nitude larger than previous methods,with an implementation that can use

97% of the Jaguar supercomputer atOak Ridge National Lab. These codesare being used to simulate the unitarygas (e.g., vortex formation) [16] and aheavy nucleus under the action of var-ious external fields. While stillexploratory, these first-time simula-tions of this kind for fermion super-fluids serve as proof of principle foran eventual treatment of fission.

Quality Control in UNEDF Integral to the UNEDF project is

the verification of methods and codes,the estimation of uncertainties, andassessment. Methods to verify andvalidate include the cross-checking ofdifferent theoretical methods andcodes (e.g., GFMC vs. AFDMC vs.NCFC), the use of multiple DFT solv-ers with benchmarking, and the con-frontation of ab initio functionals withab initio structure using the sameHamiltonian. Uncertainty quantifica-tion follows using tools for correla-tion analysis to estimate errors andsignificance. A new way to estimatetheory error bars is to use multiple

Figure 9. Calculated reaction cross-sections for protons on 90Zr as afunction of incident energy comparedto data. The solid line is the fullcalculation while the dashed curve isfrom the global optical potential [15].

Figure 8. Calculated [14] NCSM/RGMcross-section for 17 MeV neutrons on4He compared to experiment.



RG-evolved Hamiltonians and exam-ine the cutoff dependence of calcu-lated observables.

The UNEDF assessment compo-nent has required the developmentand application of statistical tools.Particularly important for potentialexperiments is the analysis of experi-mental data significance. For exam-ple, the sensitivity of two optimizedfunctionals to particular data is shownin Figure 11 [13]. Statistical tools areused to deliver uncertainty quantifica-tion and error analysis for theoreticalstudies as well as for the assessmentof new experimental data. Suchtechnologies are virtually unknown inthe low-energy nuclear theory com-munity at present, but are essential asnew theories and computational toolsare applied to entirely new nuclearsystems and to conditions that are notaccessible to experiment.

Outlook These brief highlights represent

only part of the development withinthe UNEDF project and new results

are appearing steadily. Please visitunedf.org to find further summaries,updates, and references. WhileUNEDF is in the final year of its 5-year term, its impact will be ongo-ing. Indeed, UNEDF has createdinfrastructure and interconnectionsthat are only just beginning to befully exploited. An important spin-off for the future has been the train-ing of young scientists in the newdevelopments of low-energy nucleartheory.

The worldwide impact of theUNEDF collaboration, which isunique in the field of low-energynuclear physics in its scope, size, andstructure, was evident at the 2010INPC meeting in Vancouver, whereUNEDF highlights were quoted inseveral plenary talks. While based andfunded in the United States, UNEDFcollaborates closely with foreignefforts and individual scientists shar-ing similar fundamental science goals.Such collaborations include joint soft-ware developments and benchmark-ing, and representatives of internat-ional collaborating projects attend theUNEDF annual meetings. TheseUNEDF activities have had positiveleveraging effects on our foreign part-ners, including the joint UNEDF-JUSTIPEN and UNEDF-FIDIPROefforts and a new initiative involvinglow-energy nuclear theory in France,FUSTIPEN.

High performance computing pro-vides answers to questions that nei-ther experiment nor analytic theorycan address; hence, it becomes a thirdleg supporting the field of nuclearphysics. A series of meetings onextreme scale computing in 2009identified several major researchthrusts that have a strong foundationin UNEDF achievements [20]. Theseinclude pathways to a quantitative

microscopic description of fission,computing properties of nuclei thatdetermine the r-process nucleosynthe-sis path in stars, computing propertiesof nuclei used in double-beta decayexperiments and neutrino-nucleuscross-sections for modeling super-nova explosions, and computing thetriple-alpha process that produces 12C,the nucleus at the core of organicchemistry and thus life forms. Thefuture prospects are bright!

Acknowledgments This work was supported by the

UNEDF SciDAC Collaboration underDOE Grant DE-FC02-07ER41457.

References 1. G. Bertsch et al., SciDAC Review 6

(2007) 42. 2. E. Lusk et al., SciDAC Review 17

(2010) 30. 3. P. Maris et al., Procedia Comp. Sci. 1

(2010) 97. 4. P. Maris et al., Phys. Rev. C 81 (2010)

021301(R). 5. P. Maris et al., Phys. Rev. Lett. 106

(2011) 202502. 6. V. Z. Goldberg et al., Phys. Lett. B

692 (2010) 307. 7. E.D. Jurgenson et al., Phys. Rev. Lett.

103 (2009) 082501.

Figure 11. The sensitivity of candidateEDF fits to particular data can beassessed. See Ref. [13] for details.

Figure 10. Pairing potential ofpolarized Fermi gas in an extremelyelongated trap with different aspectratios [18] calculated using nuclearcodes developed for fission.



8. G. Hagen et al., Phys. Rev. Lett. 101(2008) 092502; G. Hagen et al., Phys.Rev. Lett. 104 (2010) 182501.

9. K. Tsukiyama et al., Phys. Rev. Lett.(2011), arXiv:1006.3639.

10. S. Gandolfi et al., Phys. Rev. Lett. 106(2011) 012501.

11. M. Stoitsov et al., Phys. Rev. C 82(2010) 054307.

12. G. I. Fann et al., J. Physics: Conf. Ser.180 (2009) 012080.

13. M. Kortelainen et al., Phys. Rev. C 82(2010) 024313.

14. P. Navrátil et al., arXiv:1009.3965.

15. G. Nobre et al., Phys. Rev. Lett., 105(2010) 202502.

16. R. Senkov et al., Phys. Rev. C 82(2010) 024304.

17. A. Bulgac and M. M. Forbes, Phys.Rev. Lett. 101 (2008) 215301.

18. J. C. Pei et al., Phys. Rev. A 82 (2010)021603(R).

19. A. Bulgac and K. J. Roche, J. Phys.:Conf. Ser. 125 (2008) 012064; A.Bulgac et al., arXiv:1011.5999.

20. www.er.doe.gov/ascr/Misc/Grand-Challenges.html

RICHARD FURNSTAHL

(FOR THE UNEDF COUNCIL)Department of Physics,

Ohio State University

meeting reports


25th International Nuclear Physics Conference

From 4–9 July 2010, TRIUMF,Canada’s national laboratory for par-ticle and nuclear physics, hosted the25th International Nuclear PhysicsConference (INPC) 2010 in Vancou-ver, Canada. The triennial INPC is themain conference in the field and issupported by IUPAP (InternationalUnion for Pure and Applied Physics).This year it attracted over 750 dele-gates (including 150 graduate stu-dents) from 43 countries and coveredtopics in nuclear structure, reactions,and astrophysics; hadronic structure,hadrons in nuclei, and hot and denseQCD; new accelerators and under-ground nuclear physics facilities; neu-trinos and nuclei; and applicationsand interdisciplinary research.

The conference opened its scien-tific plenary program with a talk byP. Braun-Munzinger (GSI/EMMIDarmstadt) who highlightedprogress since the last conference inTokyo 2007, showcasing theoreti-cal and experimental examples fromaround the world. All fields werewell represented by the plenary

program and a well-attended after-noon parallel program, with over250 invited and contributed talksand over 380 posters presented. Theposter sessions were among themost lively sessions with high par-ticipation rates by graduate studentsand post-doctoral fellows.

Conferences like the INPC spanan entire discipline, fostering manyunexpected links, discussions, or col-laborations among participants. Sci-entific highlights includedpresentations in the fields of Hot andDense QCD reporting on experimen-tal and theoretical progress at theRHIC facility. The Nuclear Reactionsession provided highlights frommany new and exciting facilitiesincluding the RIKEN RIBF in Japan,and an outlook for what can beexpected from FAIR in Germany andFRIB in the United States. The questtoward the “Island-of-Stability” in theSuperheavy Element community isstill on, and new progress wasreported with the identification of ele-ment 114.

Impressive progress in the theoret-ical sector was presented as well, inparticular new ab-initio calculationapproaches. Applications of thesemethods and progress in the nucleon-nucleon interactions were presentedin the Nuclear Structure sessions,where 3-body forces interactions arenow considered state of the art. Pre-dictions of such calculations can thenbe tested by experiments, as presentedfor example for ground state proper-ties of exotic nuclei with laser experi-ments and ion trap measurements. In-beam or in-flight experiments pavethe way to even more exotic isotopeswhere new magic numbers for thenuclear Shell Model are appearing.This will also prove relevant forNuclear Astrophysics, where signifi-cant progress was achieved experi-mentally with new direct capturereactions measurements with rare iso-tope beams and background-sup-pressed facilities located inunderground laboratories. Neutronstar research and new modelingresults of core-collapse supernovaewere presented, which clearly indi-cated the need for neutrino interac-tions. Neutrinos also played a largerole in other sessions, such as the NewFacility session, were among othernew exciting projects, progress fromthe deep underground facilities werepresented. First beam results fromlong-base line oscillation experi-ments showed progress in this field,and double-beta decay experimentsare nearing first possible results,keenly awaited by not only the com-munity of nuclear physicist but manyothers as well. The FundamentalSymmetry sessions is always one ofthe highlights, where progress of

Figure 1. Before the storm: the conference venue, the Chan Centre ofPerforming Arts at the University of British Columbia.

meeting reports


Standard Model tests using atomicnuclei or nuclear physics methods areused to probe sectors complementaryto large particle physics experiments,for example atomic and neutron EDMexperiments. Recent progress wasreported in the sector of nuclear betadecay as related to the testing of theCKM Unitarity matrix, as well as theW-mass and the Weak Mixing Angle.

Talks on the muon anomalous mag-netic moment and its sensitivity forprobing “New Physics” showcasedthe burgeoning activity in the field.

INPC 2010 made a special effort toattract many graduate students and post-doctoral fellows to the conference. Forexample, TRIUMF combined its tradi-tional summer school with the U.S.National Science Foundation summer

school for nuclear physics, andoffered the school directly prior to theconference. This allowed the schoolto recruit some of the INPC delegatesas lecturers, but also gave students abroad overview to the field of nuclearphysics before the conference. Inaddition, INPC 2010 teamed up withNuclear Physics A to provided awardsto the best student oral presentationand the three top poster presentationsat the conference. An internationalpanel of judges together with mem-bers from the editorial board ofNuclear Physics A finally decided onthe following award winners among avery strong field of applicants: P.Finnlay (Guelph, Canada) for oral,and Y. J. Kim (Indiana, USA), E.Rand (Guelph, Canada), and T. Brun-ner (Munich, Germany) for posters.

The field clearly presented itself ina healthy and dynamic state, withmany young people eagerly anticipat-ing the advent of new experiments,theory, and facilities. At the end of theconference IUPAP announced theselection of the host of the next INPCconference: it will be held in 2013 inFlorence, Italy.

JENS DILLING

TRIUMF Vancouver

Zakopane Conference on Nuclear Physics, “Extremes of the Nuclear Landscape”

The Zakopane Conferences onNuclear Physics belong to one of theoldest series of conferences in the fieldof nuclear physics. Their tradition isalmost half a century old and 2010 wasthe 45th meeting in the series.

The Conference was held from 30August through 5 September, and had

185 participants who came to Zakopanefrom 50 institutions from all over theworld—70 of them were Ph.D. studentsand young researchers. The meetingwas organized jointly by the HenrykNiewodniczanski Institute of NuclearPhysics of the Polish Academy of Sci-ences (IFJ PAN) in Kraków, the Marian

Smoluchowski Institute of Physics ofthe Jagiellonian University, and theCommittee of Physics of the PolishAcademy of Sciences. This time, theOrganizing Committee was led byAdam Maj, acting as chairman, PiotrBednarczyk—Scientific secretary andMaria Kmiecik—Managing director.

Figure 2. The opening plenary talk gave highlights of progress in nuclearphysics, presented by P. Braun-Munzinger (GSI/EMMI) in the beautiful ChanCentre auditorium at the University of British Columbia.

meeting reports


The title “Extremes of the NuclearLandscape,” which was chosen for theConference, indicated that the scien-tific program would cover a broadspectrum of forefront research activi-ties presently ongoing in the area ofnuclear physics. This ambitious enter-prise was carried on by the organizerswith support from the Board of Con-veners that gathered distinguished col-leagues with expertise in various areasof the field. Each convener, acting inclose collaboration with the organizers,prepared a specific program for his/hersession by inviting lecturers and select-ing contributions for oral presenta-tions. According to the tradition of theZakopane Conferences, during theconstruction of the scientific programspecial attention was paid to offeringthe graduate students and youngresearchers enthusiastic and pedagogi-cal overviews of the most recentresearch subjects in Nuclear Physicsfrom both the theoretical and theexperimental points of view.

The Conference began with thetwo keynote talks delivered by WalterHenning and James Vary—bothspeakers alluded to a unifying theme,“extremes of the nuclear landscape.”

Walter Henning presented a broadoverview of recent results from theexisting radioactive beam facilitiesand illustrated progress in the con-struction of the new RIB researchcenters. In a similar manner, but withfocus on the theory aspects, JamesVary concentrated on prospects ofgetting insights into the origins ofnuclear structure based on the funda-mental approach tied to QCD.

The topics signaled in Vary’s talkwere discussed thoroughly during thefirst regular session that was convenedby Witek Nazarewicz (Tennessee/Warszawa) under the title “ComputingAtomic Nuclei: Frontiers of NuclearStructure Theory.” In this session, lec-tures were given by Achim Schwenk(TRIUMF/Darmstadt), Morten Hjörth-Jensen (Oslo), Stuart Pittel (Delaware),Frederick Nowacki (Strasbourg),Dario Vretenar (Zagreb), and WojtekSatula (Warszawa).

The review of the latest experimen-tal results in nuclear structure physicsstarted with the heaviest nuclei—thispart was led by Matti Leino (Jyväskylä).Here, the lectures, largely focused onspectroscopic and radiochemical inves-tigations of heavy elements, were pre-

sented by Dieter Ackerman (GSI),Sergey Dmitriev (Dubna), and PaulGreenlees (Jyväskylä).

The latest achievements in thestudy of proton-rich nuclei were pre-sented in the session organized byMike Bentley (York) in which theinvited speakers were: Bob Wadsworth(York), Dirk Rudolph (Lund), TommiEronen (Jyväskylä), and BertramBlank (Bordeaux).

A wealth of information on neu-tron-rich nuclei, which had beenrecently accumulated in experimentsusing radioactive beams or new reac-tion product detection techniques,provided a basis for the part that wasconvened by Faical Azaiez (Orsay).The list of speakers included:Hiroyoshi Sakurai (RIKEN), DanielBazin (MSU), Didier Beaumel(Orsay), Krzysztof Rykaczewski(ORNL), Reiner Krücken (München),and Giacomo de Angelis (Legnaro).

Gamma-ray spectroscopic studiesof neutron-rich nuclei, although withemphasis on the reaction mechanisms,were the main focus in the series oftalks named “Nuclear Reactions andSpectroscopy with Novel Tech-niques.” The content of this part was

meeting reports


constructed by Marek Lewitowicz(GANIL) who invited Silvia Leoni(Milano), Wojtek Królas (Kraków),Navin Alahari (GANIL), and Hans-Jürgen Wollersheim (GSI).

Closely related to the aforemen-tioned topics presented were theissues discussed in the session“Nuclear Lifetimes and Collectivity”that was led by Hans Geissel (GSI).Here, the invited lecture was given byWolfram Korten (Saclay).

The part titled “CollectiveModes,” conducted by Angela Bracco(Milano), was devoted to studies ofhigh-lying collective excitations builton both ground and highly excitedstates. Of main interest here were thepygmy resonances in neutron-richnuclei, the compression-mode giantresonances, prompt dipole gammaemission as well as the soft dipolemodes and the tidal-wave mode ofcollective excitations; all this was pre-sented by Takashi Nakatsukasa(RIKEN), Sunniva Siem (Oslo),Franco Camera (Milano), UmeshGarg (Notre Dame), Indranil Mazum-dar (Mumbai), and Walter Reviol (St.Louis).

The “Structure of Light Nucleiand Astrophysics” session, convenedby Tohru Motobayashi (RIKEN),while introducing the scientific activ-ity on nuclear clustering also showeda broad area of research on the bound-ary between nuclear physics andastrophysics. The list of invitedspeakers included Hisashi Horiuchi(Osaka), Christian Beck (Stras-bourg), David Jenkins (York), MosheGai (Yale), and Silvio Cherubini

(Catania). This part of the meetingended with two talks that illustratedthe construction status of the tworadioactive beam facilities in Europe:Marek Lewitowicz (SPIRAL2) andZbigniew Majka (FAIR).

A separate gathering had as theobjective the studies that do notbelong to the main stream of researchactivity in low-energy nuclear phys-ics, although they are of interest to thebroad nuclear physics audience. Thecontent was organized by ChristophScheidenberger (GSI) under the title“Beyond Nuclear Physics.” Invitedpresentations were given by JosefPochodzalla (Mainz), Jürgen Gerl(GSI), Andrzej Rybicki (Kraków),Marek Kowalski (Kraków), Peter Thi-rolf (München), and Ludwik Pien-kowski (Warszawa).

A special event of the Conferencewas The Midnight School preparedand tutored by Jerzy Dudek (Stras-bourg) under the title “Symmetries inNature–Symmetries in Nuclei.” Thishappening was addressed to the verygeneral public. A unifying themewere mysterious numerical relationsobserved in Nature together with thewell-known symmetries establishedin the world of atomic nuclei.

One of the evenings was entirelydevoted to the poster session. The ses-sion was a very energetic event withinnumerable technical conversations,which extended far beyond the sched-uled time—all of which are indicatorsof stimulus and strong interest in ourfield.

The Conference had the pleasureto host as a special invited speaker

Michal Heller, the 2008 TempletonPrize Laureate. The special guestdelivered a lecture devoted toGeorges Lemaître’s contribution tothe foundation of modern relativisticcosmology.

Altogether, the scientific programconsisted of 45 invited talks, 51 oralpresentations, and the poster sessionwith 49 contributing posters.

Zakopane Schools have a reputationof offering opportunities for intenseinteraction between graduate students,young researchers, and senior scientists.The Zakopane Conference 2010 gavemany occasions for such interactionsthrough the discussions during scientificsessions as well as during the traditionalexcursions to the most scenic places inthe area of Zakopane and the TatraMountains. Even the weather condi-tions, which were not the most favor-able for hiking (putting it straight, formost of the time it was raining cats anddogs), contributed very positively to theoverall atmosphere of the event bykeeping people together, thus enablingmany long discussions to take place. Itwas visible that the scientific and socialparts of the Conference fantasticallycomplemented each other, thus provid-ing yet another example of the impor-tance of both cognitive and humanaspects of Science.

The organizers hope to see you atthe next Zakopane Conference in2012 (27 August–2 September).

BOGDAN FORNAL

IFJ PAN, Kraków

meeting reports


The International Symposium on New Faces of Atomic Nuclei

The International Symposium onNew Faces of Atomic Nuclei washeld on 15–17 November 2010 inOkinawa, Japan, in order to discussfuture directions of nuclear physics atthe 80th birthday of Professor AkitoArima. The venue was the OkinawaInstitute of Science and Technology(OIST), which has recently been con-structed in the main island of Oki-nawa for the promotion of science andtechnology in Okinawa in an interna-tional atmosphere. Akito Arima is oneof the co-chairs of its Board of Gover-nors, and has contributed to create thisatmosphere.

This symposium was devoted tovital discussions on future directions ofnuclear physics. Atomic nuclei carrymost of the mass (weight) of all materi-als in and on the earth, and are ultimatesource of all energies causing phenom-ena there. The complete understandingor full usage of atomic nuclei is, how-ever, yet to come. In other words, newfaces of atomic nuclei are still emerg-ing. Recent progress of nuclear physicsindeed brings us to unexplored frontiersof science. Thus, the name “NewFaces” came up again.

Such new faces have not comefrom scratch but from various effortsmade over decades, to many of whichAkito Arima has contributed substan-tially. The symposium started with theopening greetings by Ms. H. Shou, aformer vice governor of Okinawa, rep-resenting also the OIST, and myself asthe chair of the organizing committee.The first scientific session was “IBMtoday,” where recent developments ofthe Interacting Boson Model (IBM)were presented. Iachello (Yale) talkedabout a possible application of the IBMto double beta decay. Van Isacker(GANIL) showed a new algebraicapproach to peculiar properties of N = Znuclei. Nomura (Tokyo) then reportednew development for the microscopicfoundation of IBM, validating it bycomparison to experiments. All referredto Arima’s initiatives at the early stageof IBM studies.

In the second session, Sakai(RIKEN) introduced activities toorganize nuclear physics activities inAsia, by creating Asian Nuclear Phys-ics Association (ANPhA). This talk isquite appropriate, as Arima has beenvery keen in developing nuclear phys-

ics in Asia. Gales (GANIL) reviewedthe new era of physics with exoticnuclei with SPIRAL2 at GANIL, fol-lowed by a talk by Suzuki (Nihon) onnuclear astrophysics.

In the afternoon, Sakurai (RIKEN)gave an overview on RIKEN’s nuclearphysics program, focusing on therecently built RIBF accelerator complex,and Nazarewicz (ORNL) presentedanother overview from the theoreticalside with emphasis on superheavy ele-ments. Three theoretical talks by Meng(Beijing), Kamimura (RIKEN), andKanada-En’yo (Kyoto) followed.

Tonomura (Hitachi/OIST) was oneof the guest speakers, and visualizedquantum phenomena observed withelectrons. Asakawa (Osaka) and Braun-Munzinger (GSI/EMMI) discussedQGP theoretically and experimentally.Tamura (Tohoku) introduced the cur-rent status of J-PARC, while Shimizu(Sophia) discussed hadron resonances.

On the second day, Talmi (Weiz-mann), Barrett (Arizona), and Shimizu(Tokyo) discussed classic and contem-porary issues of the shell model.Weidenmueller (Heidelberg) talkedabout nuclear excitations by strong laserpulses. We had presentations byyounger generations such as Kawabata(Kyoto), Hinohara (RIKEN), and Ishii(Tokyo) from clustering to lattice QCD.Hjorth-Jensen (Oslo) summarized thecurrent status of many-body problemsof nuclear structure.

We had Interdisciplinary Linkssession then. It was started by a videogreeting by Dorfan, who has been ahigh-energy physicist at Stanford andthe president-elect of OIST. Casten(Yale) gave a remarkable introduction

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of nuclear physics to the general audi-ence, and Frois (CEA) showed howphysics and society can be linked onthe energy issue, by showing a nicemovie. Skoglund (OIST) gave a talk“Freeze the macromolecules to seethem dance!”

In the second part of the Interdis-ciplinary Links session, Tsuchiya(Ryukyus), who is an oceanic biolo-gist, explained how biological interac-tions work in coral reefs. Balantekin(Wisconsin) went up to the sky, talk-ing about the role of nuclear physicsin understanding the universe and theorigin of elements. Hirao (ANTM)has been working on ion-beam ther-apy and presented impressive slides tohow nuclear beams cured cancer formany patients.

We had a very lively and pleasantbanquet celebrating Arima’s 80th birth-day at the Intercontinental Manza BeachResort. Many former students of Arimawere present. In the same year, Arimawas awarded the Order of Culture, whichis only award granted by the Emperor.This was celebrated also because a

nuclear physicist was awarded the Orderof Culture for the first time.

On the third day, recent develop-ments in the nuclear shell model werereported by Brown (MSU), Ginocchio(LANL), Utsuno (JAEA), and Suzuki(Niigata). Zhao (Shanghai) is stillworking with Arima, and talked abouttheir collaborative work on quantumchaos, Kajino (NAO) talked aboutneutrinos, Bentz (Tokai) discussednuclear magnetic moments, which isanother favorite subject of Arima.Sugawara-Tanabe (Otsuma) gave thefinal talk on Elliot SU(3) and triaxial-ity. Horiuchi (RCNP) has given awarm closing remark.

We see that the range of the talksubject is quite wide, reflecting the vari-ety of the contributions made by Arima.We believe that the participants per-ceived good ideas on the future ofnuclear physics. The proceedings willbe published from AIP as one of its con-ference proceedings series.

The organizers were W. Benz(Kanagawa), H. Horiuchi (Osaka), M.Oka (TIT), T. Otsuka (chair, Tokyo),

and N. Yoshinaga (Saitama). Thetotal number of participants was 62,including 6 from the United States, 3from France, 2 from Germany, 2 fromChina, and 1 each from Israel andNorway. This symposium has beensupported by the OIST, the EFES pro-gram of JSPS, the Inoue ScienceFoundation, and the CNS of the Uni-versity of Tokyo.

Waltzing to the Nuclear Limits: A Symposium in Honor of Lee Riedinger

A conference “Waltzing to theNuclear Limits—A symposium inhonor of Lee Riedinger,” was held atthe Sea Pines resort on Hilton HeadIsland, South Carolina, USA, 25–27February 2011. Attended by about 80people from the United States andabroad, the conference featuredinvited talks and a poster session cov-ering a wide range of topics in con-temporary nuclear structure physics,with special emphasis on those repre-senting extremes in nuclear structure,such as exotic nuclei far from stability

and nuclei at very high spin. The con-ference name has a dual connotation.It recalls Maria Goeppert Mayer’sdescription that nuclei are “built uplike an onion in layers, with the pro-tons and neutrons revolving aroundeach other and spinning in orbit, likecouples in a waltz around a ballroom”as well as referring to Lee Riedinger’slove of dancing (albeit not specifi-cally waltzing).

Talks focused on a variety of sub-jects including broken symmetries,new collective modes, nuclei at high

and ultrahigh spins, isomers, shellstructure in the Sn region, the fragilityof magicity, neutron transfer studiesof exotic nuclei, quantum phase tran-sitions, moments and radii, fissionproduct studies, lifetime measure-ments, the role of simulations in sci-ence, and facilities and instrumentssuch as ATLAS, HRIBF, NSCL,GANIL/SPIRAL 2, FRIB, ELI,GRETINA, and AGATA. New devel-opments in all these areas attest to thehealth and vitality of the field and tothe advances being made due to

TAKAHARU OTSUKA

University of Tokyo

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technological revolutions in accelera-tor design, instrument capability, andcomputational power. Together, theseare launching nuclear structure phys-ics into a new era, focusing on territo-ries of the nuclear chart never beforeaccessible.

Lee Riedinger’s many physicsinterests and achievements were oftencited, ranging from pioneering earlywork on band mixing, to a wealth ofstudies of high spin nuclear physics,as were his more recent interests inenergy, his community service as aformer chair of the DNP, advisor toSenate Majority Leader HowardBaker, his long-term role as Federalbudget guru to the nuclear physicscommunity, and his important role inthe quest to provide important iso-topes to the nuclear and medical com-munities. Many of these contribut-ions, as well as his sporting, dancing,and other pursuits were highlighted ina friendly “roast” at the ConferenceBanquet attended by over a hundredpeople, including his wife Tina, anddaughters Jen and Kara, as well as

many of Lee’s former students andpost-docs. About 20 of Lee’s col-leagues and friends offered storiesand reminiscences of Lee and hisfamily. Some of Lee’s many and var-ied career achievements are summa-rized in the following couplets(slightly edited) taken from a longerpoem written for the occasion:

Using Sodium Iodide even andGermanium,

Lee studied nuclei like Samarium. With Joe and Noah, he studied

bandmixing a ton And with that our eternal respect

he won, With a landmark paper in PR 179 That was a work ever so fine. In Copenhagen town at the Bohr

Institute Lee’s physics really began to take

root.What else could be in store Listening to Ben and Aage Bohr? Bandcrossing, moments of iner-

tia, and alignments galore Having seen one, he wanted many

more!

Where would UT and ORNL bewithout Lee?

He has guided both for physicsand energy,

As professor and administrator, Teacher, and inspired mentor. For helping our community Lee

has had a flair From budget guru to DNP Chair.

The atmosphere of the conferencewas warm and friendly, with new sci-ence and old remembrances, as well asthe traditional Gordon Conference–likesoftball game. All the attendees areeagerly awaiting Lee’s hundredthbirthday to have another conference.

ANI APRAHAMIAN

Notre Dame

MIKE CARPENTER

Argonne National Laboratory

RICK CASTEN

Yale University

JOLIE CIZEWSKI

Rutgers University

DARYL HARTLEY

U.S. Naval Academy

FILIP KONDEV

Argonne National Laboratory

WITEK NAZAREWICZ

University of Tennessee and OakRidge National Laboratory

MARK RILEY

Florida State University

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Official Release of the NuPECC Long Range Plan 2010

The Nuclear Physics EuropeanCollaboration Committee (NuPECC)establishes a full review of research inall fields of nuclear physics that ispublished every five years. The workon the “2010 Long Range Plan” hasstarted in the summer of 2009 and thefinal report has been released 9December 2010 in an official cere-mony that took place at the RoyalAcademy in Brussels.

The document is divided into sixsubdomains: hadron physics, phases ofstrongly interacting matter, nuclearstructure and dynamics, nuclear astro-physics, fundamental interactions, andnuclear physics tools and applications.Leading scientists of each subject wereasked to contribute to each chapter.

The aim of this document is toreview the recent achievements, put-ting into evidence outstanding results,and at the same time to identify themain lines of research for the nextdecade and to foresee the hottest top-ics. Different strategies are proposedto develop medium and long-termplans, with an European perspectiveand put it in a global context.

The elaboration of the long rangeinvolved the whole communitythrough two meetings organized inFrankfurt October 2009 and inMadrid in May 2010. The goal of themeetings was to invite the European

Nuclear Physics community, some6,000 scientists, to express its view onthe development of Nuclear Physicsin the next decade and to bring itsinput for a coherent development ofthe field. The document was prepared

during this period by six workinggroups, one for each subdomain thathas been identified, under the supervi-sion of NuPECC.

The final document was releasedin a ceremony in Brussels under the

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auspice of the Belgian presidency ofthe European Union. It was open byan official representative of the fed-eral minister Magnette, in charge ofenergy and environment. Talks weregiven by representatives of organiza-tions supporting and organizingresearch in Europe, Drs. Dr. BeatrixVierkorn-Rudolph Chair of the Euro-pean Strategy Forum on ResearchInfrastructures, ESFRI, Dr. MarcHeppener for ESF, and Dr. ChristianKurrer for Commission’s Directorate-General for Research. The long-range

plan itself was presented by theNuPECC chairman, Dr. Gunther Ros-ner. A scientific view on the evolutionof nuclear physics in the next decadeswas the subject of the last talk, givenby Dr. Jean-Paul Blaizot.

A special effort was made topresent the long-range plan in a formaccessible to the largest possible audi-ence. To this effect, a booklet waswritten by science writers under thesupervision of NuPECC and a shortpedagogic movie was prepared by acommunication agency to present the

status and the future of nuclear phys-ics. All these documents are accessi-ble on the NuPECC website: http://www.nupecc.org/index.php?display=lrp2010/main

PAUL-HENRI HEENEN

Université Libre de Bruxelles

MARIA JOSÉ GARCIA BORGE

CSK, Madrid

NuPNET: Successful Launch of NuPNET’s First Common Call for Joint Transnational Activities in Nuclear Physics

On 14 February 2011, NuPNET—the joint European network forNuclear Physics Infrastructures—launched its first common call forjoint transnational activities in threeimportant research areas of NuclearPhysics. With a total budget of notless than 3.4 million Euros, this call isco-funded by 12 agencies responsiblefor the funding of Nuclear Physics in10 European countries (http://www.nupnet-eu.org/wps/portal/launch-of-nupnet-call.html).

NuPNET—the ERA-Net forNuclear Physics infrastructures (http://www.nupnet-eu.org/)—is a three-yearproject launched on 27 March 2008and financed by the European Com-mission to the tune of 1.3 millionEuros. Coordinated by IN2P3/CNRS,this European initiative incorporates18 funding agencies/organizationsfrom 14 European countries, 1 associ-ate member and NuPECC, who actsas NuPNET’s “Scientific AdvisoryBody.”

According to the “NuPNET Report2010” (led by I. Reinhard, PT-GSI,Germany, http://www.nupnet-eu.org/wps/portal/nupnet-report-2010.html), the 14“NuPNET” countries provide morethan 90% of the total funding in NuclearPhysics in Europe. NuPNET can thusbe considered as being truly representa-tive of the European map in NuclearPhysics funding and as offering the bestframework conditions to reach its prin-cipal aim: enabling the nuclear physicsfunding agencies to pilot joint transna-tional activities themselves.

In Europe, the facilities for nuclearphysics are mostly operated by labo-ratories financed by national fundingagencies and universities. Over thenext decade, a number of these willsee major upgrades, including theconstruction of a new generation ofinfrastructures accepted by ESFRI astruly pan-European ventures (i.e.,FAIR and SPIRAL2), which isalready well under way. The nuclearphysics community in Europe as well

as worldwide is fragmented when itcomes to financing joint actionstogether and it appears that not onlythe funding systems of various coun-tries and institutions are different butso are their national priorities. This iswhere NuPNET comes in.

Once the “NuPNET Report 2010”was done, a list of opportunities forjoint activities in Nuclear Physicsresearch was defined (led by A.Bracco, INFN, Italy), the formal andlegal barriers of the national fundingsystems were analyzed (carried out byA. Ostapczuk, NCBiR, Poland), and afunding action plan elaborated andapproved (led by N. Alamanos and B.Saghai, CEA, France).

After a survey of the existing cooper-ation tools (led by Ch. Stoyanov,INRNE, Bulgaria), all NuPNET memberinstitutions were consulted at variousstages to define a short-list of viable top-ics in view of NuPNET’s Common Call.And so the next step “Selecting jointactivities at a transnational level” was

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achieved under the leadership of JoséBenlliure (MICINN, Spain).

This major step was accomplishedby the representatives from all the 18NuPNET member institutions/organi-zations during the meeting of theNuPNET Governing Council atCNRS headquarters in Paris on 15October 2010, at which the priorityresearch themes in Nuclear Physics inview of a common call for proposalswere decided. Finally, a list of threetopics was voted unanimously and theNuPNET Consortium decided to opena first common call for proposals as apilot action, which was indeedlaunched in February.

The three topics of this first NuP-NET Call were: (1) R&D on newdetector technologies in nuclearphysics: Gamma and neutron detec-tion technologies based on new scin-tillation materials and new photo-sensors (APDs, SiPMs…). Siliconand micropatterned gas trackingdetectors (GEM, Micromegas) forlow and high energy applications.

Large-area diamond detectors forbeam monitoring or timing. (2) R&D onEURISOL technologies: acceleratorcomponents, targets, and ionsources. (3) Targeted action onnuclear structure and reactionstheory. Twelve funding agenciesfrom 10 countries participate in thisfirst NuPNET Call: Bulgaria(INRNE), Finland (HIP and JY),France (CEA and CNRS/IN2P3),Germany (BMBF), Italy (INFN), theNetherlands (RuG), Poland (NCBiR),Romania (IFIN-HH), Spain (MICI-NN), and the United Kingdom(STFC). The national contributions toa virtual common pot of this firstNuPNET Call amount up to 3.4 mil-lion Euros. Proposals were submittedelectronically by 22 April 2011. Eligi-ble proposals were transmitted toevaluators, who examined them withregard to seven figures of merit (sci-entific relevance, strategic fit to call,international competitiveness, etc.).

On 7 July 2011 the Panel Boardwill meet and decide. By end of July

the results of the evaluations will beknown and one expects the start of theselected joint activities by autumn2011.

The NuPNET Consortium askedfor a prolongation of the project,although no additional funding fromthe EU Commission is expected.Upon consultation, the EU Commis-sion agreed to prolong the NuPNETproject by nine months, until the endof November 2011. This new deadlinegives NuPNET the opportunity tocarry out its first call under the verybest auspices. Moreover, thanks to thecommitment of the participatingagencies in the call, the ambition ofall the members of the NuPNET con-sortium will become a reality: indeed,the first nuclear physics projects co-funded by the participating NuPNETagencies are planned to start in the fallof 2011.

SYDNEY GALÈS

AND DOROTHÉE PEITZMANN

NuPNET Co-ordination TeamIN2P3/CNRS

CologneAMS becomes OperationalIn 2007 the Institute für Kern-

physik (IKP) together with the Insti-tute of Geology & Mineralogy of theUniversity of Cologne won a nationalDFG contest to operate a new nationalcentre for Accelerator Mass Spectros-copy CologneAMS (http://www.cologne-ams.de) [1].

It was intended to improve theexperimental conditions especially forthe German scientists who apply theAMS technique for their researchwork. It was demanded that the facil-ity is suited for the spectrometry of allstandard cosmogenic nuclides like

10Be, 14C, 26Al, 26Cl, 41Ca, 129I, and inaddition to measure sensitively heavyions up to 239U and 244Pu. The heart ofthe AMS setup is a 6 MV Tandetronaccelerator to which a low energymass spectrometer with a negative ionsource, capable to load 200 samples,and a high energy mass spectrometerwith two detector systems for themeasurement of the radioactive iso-topes is attached. One of these detec-tor systems is equipped with a secondfoil stripper unit followed by a 120°bending magnet to allow for an effec-tive isobar suppression [2] to reduce

overloading the ionisation chamberby isobar contaminations.

In May 2010 the accelerator wasdelivered to Cologne. In a spectacularaction it was brought into the secondbasement floor of the completely ren-ovated underground laboratory of theIKP (Figure 1). The operation of theAMS facility is completely indepen-dent from experiments performed atthe 10 MV Tandem [3] which islocated in the first basement floor ofthe accelerator area. After the assem-bly during the summer the AMSinstallation and the completely

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renovated accelerator laboratory wereinaugurated on 1 October in thecourse of a three-day celebration ofthe 50 years of existence of the IKP(Figure 2). These festivities includeda two day symposium attended by 150friends of the IKP, an alumni evening

with 300 participants of all ages andan open door day for the generalpublic.

Since then the function tests of theindividual components of the AMSsetup could be successfully completedand first test measurements for 14Cand 36Cl as well as for other isotopesproved that the ambitious design val-ues could be met. After the summervacations we expect the facility to beopened for its first users. The firstprojects from local groups will bedevoted to geological surface investi-gations and astrophysical problems.

Recently an agreement for cooper-ation was signed between the Univer-sity of Cologne and the GermanResearch Centre for Geosciences,Potsdam (GFZ). Within the frame-work of this agreement the GFZ willinvest 850 k€ for further develop-ments of the AMS facility. In returnthis investment will be compensatedby reduced charges demanded for themeasurement of samples from GFZprojects.

Special laboratories for samplepreparation will be built at the Insti-tute for Geology & Mineralogy wherea complete service for sample prepa-ration will be offered for external

users in the future. The members ofCologneAMS are ready to maximizetheir efforts to make the new centerone of the leading laboratories in thefield of AMS.

References 1. A. Dewald, J. Jolie, and A. Zilges,

Nucl. Phys. News 18(3) (2008) 26. 2. M. Klein, A. Dewald, et al., ECAART,

Conference proceeding, 2010. 3. J. Jolie, H. Paetz gen. Schieck, J.

Ebert, and A. Dewald, Nucl. Phys.News 12(1) (2002) 4.

ALFRED DEWALD AND JAN JOLIE

University of Cologne

Storage-Ring Facility at HIE-ISOLDE Stored secondary beams enable a

wide range of nuclear physics experi-ments as has been proven in experi-ments over the last two decades atthe cooler-storage ring ESR in Darm-stadt and since very recently also atthe CSRe ring in Lanzhou [1, 2].These facilities, however, are spe-cialized on experiments at relativisticenergies. Efforts are presently under-

taken to employ the existing storagerings also for nuclear physics experi-ments at lower energies, which inevi-tably requires the still inefficient andtime consuming slowing down ofstored ion beams. Therefore it is ofinterest to explore the possibility ofinstalling a storage ring at an ISOLfacility which naturally deliverslow emittance low energy beams.

A dedicated workshop(TSR@ISOLDE) has been organizedat the Max-Planck-Institute forNuclear Physics (MPIK) in Heidel-berg on 28–29 October 2010. Theworkshop has collected about 50 par-ticipants from all over the world. Newphysics ideas that can be enabledemploying a low-energy storage ringat ISOLDE have been discussed. As a

Figure 1. Delivery of the 6 MVTandetron.

Figure 2. Inauguration ceremony ofthe new AMS installation.

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result, a Letter of Intent has been sub-mitted to the ISOLDE and NeutronTime-of-Flight Committee, whichwas positively evaluated in February2011 [3].

It is suggested to move the existingheavy-ion storage ring TSR to HIE-ISOLDE. The heavy-ion storage ringTSR is in operation at MPIK since1988 (Figure 1). The circumference ofthe TSR is 55.4 m and its maximalmagnetic rigidity is 1.5 Tm. Each ofthe four symmetric focusing periodsconsists of two 45° dipole magnets,five quadrupole magnets, and threesextupole magnets. A schematic viewof the TSR ring is shown in the fig-ure. The TSR has four 5.2 m longstraight sections which offer idealconditions for setting up differentexperiments. The electron coolerallows achieving stored beams withextremely small horizontal and verti-cal emittances. A dedicated ultra-cold electron target has been devel-oped in the TSR for high-resolutionexperiments with electrons. Also thelaser cooling can be applied to aselected number of heavy ion spe-cies. The TSR has an RF resonator

that can be used to accelerate ordecelerate stored beams. A peculiarproperty of the TSR is a highmomentum acceptance of about±3%, which may be used for storingexotic ions in several charge states ordifferent radioactive nuclides withsimilar mass-over-charge ratios. Anoverview of stored beam intensitiesand beam lifetimes achieved in theTSR can be found on the TSRwebpage [4].

New physics ideas for possible in-ring experiments at HIE-ISOLDEhave been suggested in the LOI. In thefollowing we briefly sketch them:

• Experimental information on cap-ture reactions (p,γ) and (α,γ) isvery scarce and is so far restrictedto stable isotopes. The storedbeam is intersected by an internalgas-jet target and the recoils aremeasured with high efficiencyafter a bending magnet. The highbeam intensities achieved by accu-mulation in the TSR can allowmoving away from the stabilityreaching νp- and later rp-processnuclei.

• One- and two-nucleon transferreactions, due to their selectivity,provide unique information onnuclear structure. The secondarybeams from HIE-ISOLDE can beefficiently stored and cooled in theTSR. The low gas-jet target thick-ness is compensated by the recir-culation and accumulation of ions.Owing to the excellent beamenergy definition and the absenceof straggling in the target, a supe-rior energy resolution is expected.

• Atomic charge states can dramati-cally modify nuclear decay con-stants. Investigations of nuclearhalf-lives as a function of atomiccharge states and of spin-parities

for the parent and daughter nucleiare proposed. Such experimentscan be used, for instance, toaddress the electron screening inbeta decay.

• It is predicted that 20–30% of 7Bein the core of the Sun is present ashydrogen-like ions. However, thehalf-life of hydrogen-like 7Becould not be measured up to now,which will be feasible atTSR@ISOLDE.

• Nuclear isomeric states are impor-tant probes to explore nuclearstructure. Owing to the sensitivityto single stored ions, the storage-ring mass spectrometry is a uniquetool to study such long-lived rarenuclear species.

• Di-electronic recombination (DR)is a well-established atomic phys-ics research program at the TSRand the ESR. A broad scientificprogram can be pursued atISOLDE, where isotopic or/andisotonic shifts can be measuredthus providing information onnuclear charge radii. Furthermore,using resonant character of DR,purification of beams in ground oralternatively isomeric states is fea-sible, in principle. Experimentswith such purified beams may besuitable for studies on laser inter-action with the nuclei or for thesearch of predicted Nuclear Exci-tation by Electron Capture(NEEC) phenomenon.

• Beta beams are today one of thepossible long baseline facilities toexplore neutrino properties, pri-marily neutrino oscillation physicsincluding CP violation in the lep-tonic sector. The (anti-)neutrinosare produced by acceleration andfinal storage of beta-decayingisotopes. The TSR@ISOLDE canbe used as a versatile tool to

Figure 1. A schematic view of theheavy-ion storage ring TSR [4]. Formore details see text.

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investigate different technical asp-ects. One of the key studies beforea full-scale experiment is envis-aged is the efficient productionand storage of 6He/18Ne or 8Li/8Bion beams.

• Last, but not least, the high resolu-tion of storage rings may beemployed for cleaning the ionbeam from isobaric contaminants.

The realization of the proposedproject requires several improvementsof the present REX- ISOLDE facility.These improvements include anupgrade of the present REX-EBIS to aSuper-EBIT. Moreover, the TSR ringneeds about 20 m × 20 m area for

installation, which inevitably requiresan extension of the ISOLDE experi-mental hall. Technical aspects of therealization of the project are beingpresently worked out in detail by thecollaboration.

References 1. B. Franzke, H. Geissel, and G. Münzen-

berg, Mass Spectrom. Rev. 27 (2008)428

2. Yu.A. Litvinov & F. Bosch, Rep.Prog. Phys. 74 (2011) 016301

3. A. Andreyev et al., “Storage ring facilityat HIE-ISOLDE,” LOI to INTC, 2011.

4. Ion Storage Ring TSR, http://www.mpi-hd.mpg.de/blaum/storage-rings/tsr/index.en.html

KLAUS BLAUM

Max-Planck-Institut fürKernphysik

YURI A. LITVINOV

Max-Planck-Institut fürKernphysik

GSI Helmholtzzentrum fürSchwerionenforschung

From Proton Beam Eye Radiotherapy to a Scanning Proton Gantry—Nuclear Physics and Hadron Radiotherapy in Krakow, Poland

On 18 February 2011 the protonradiotherapy treatment has been com-pleted for our first two ocular patientsat the Institute of Nuclear Physics ofthe Polish Academy of Sciences (IFJPAN) in Kraków, Poland. This wasthe first time proton radiotherapy hasbeen made clinically available topatients in Central Europe. A 38-year-old male and a 42-year female patient,both suffering from eye melanoma,underwent a series of four fractions ofirradiations by a 60 MeV proton beamfrom the in-house-developed AIC-144 cyclotron. Nuclear physicists col-laborated with physicians from theDepartment of Ophtalmology andOphtalmic Oncology of the JagiellonianUniversity’s Collegium Medicum and

Figure 1. The optical bench and patient treatment chair of the protonradiotherapy facility at IFJ PAN (the beam enters from the far right toward theviewer).

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from the Centre of Oncology inKraków. Thus, the clinical trial withinwhich a total of ten patients will betreated in Kraków in 2011, has nowbegan. The facility will next be usedfor regular treatment of eye-cancerpatients.

The Henryk Niewodniczaski Insti-tute of Nuclear Physics has had quitea long tradition in hadron radiother-apy. Between the years 1976 and1994, 550 patients with cancerslocated in the head-and-neck or breasthad been treated with a beam of fastneutrons produced on a thick beryl-

lium target using 12 MeV deuteronsaccelerated by the IFJ’s U-120 cyclo-tron. This cyclotron was later replacedby the AIC-144 isochronous cyclo-tron in-house-designed at the IFJPAN and adapted to proton radiother-apy between 2008 and 2010. Thebeam delivery system and treatmentroom were also in-house designed andbuilt. Our 60 MeV proton radiother-apy facility, the only one in Poland (a40-million country) and the first tooperate in Central-Eastern Europe, isnot only able to treat all Polish ocularmelanoma patients (some 100 cases

per year) but also patients in neigh-boring European countries.

Why are protons so useful in can-cer radiotherapy? Protons are able todeliver a much higher dose of ioniz-ing radiation to the tumor volume andare able to better spare the neighbor-ing critical organs or healthy tissuesthan other radiotherapy modalities.This is of particular importance topediatric patients in whom the possi-ble occurrence of secondary radia-tion-induced cancer should beminimized. Protons of initial energiesranging between 60 MeV and 250MeV when stopping in the irradiatedtissues, will deposit most of theirenergy (or dose) at their stoppingends, a phenomenon known as theBragg peak. Also, unlike in photonbeams, proton ranges are extremelywell defined by their initial energy,thus critical organs or healthy tissuesimmediately behind the tumor volumecan be spared by carefully adjustingthe proton energy. Moreover, theentrance dose of a proton beam islower than that of any megavolt pho-ton beam, thus further sparing tissuesupstream of the irradiated tumorvolume.

The range of 60 MeV protons inwater is about 30 mm, which is suffi-cient to treat tumors in the eye-ballbut to reach deeper located tumorselswehere in the body higher protonenergies are needed, to be suppliedby more powerful (and more expen-sive) accelerators. Poland, as a newmember ot the European Union isreceiving some 60 billion Euro overthe years 2007–2013, for recon-structing its infrastructure. Of thissum, IFJ PAN received about 50 M€

(85% from EU structural funds and15% from Polish government) tofinance the instalation in Krakow ofa Proteus C-235 230 MeV proton

Figure 2. A preliminary architectural concept of the new National Centre forHadron Radiotherapy in Kraków to be operational in 2014. The IBA C-235Proteus cylotron will produce a 230 MeV proton beam for proton radiotherapyand research in nuclear physics. The proton gantry with scannnig beam will beused for advanced cancer treatment.

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cyclotron, produced by the BelgianIon Beam Application (IBA) com-pany. Construction of the new cyclo-tron building (National Centre ofHadron Radiotherapy—CyclotronCentre Bronowice; Figure 2) withexperimental and treatment roomsbegan on 17 March 2011, to be com-pleted by the end of the year 2013.

To be able to deliver beams ofthese high-eneregy protons to anytumor location in the patient’s body, agantry is needed. The tender for an

up-to-date radiotherapy treatmentroom with a gantry-rotating beam willbe announced within a month. Thegantry is a huge construction, 11meters in diameter and weighing 150tons. It carries the beam-bending mag-nets and is able to aim the beam withsum-millimeter precision. We expectthis complex, called the CyclotronCentre in Bronowice, to begin treatingpatients in 2014.

Besides the proton therapy, anuclear physics research program is

planned to be carried on. It will includeamong others the gamma-ray spectros-copy (giant resonances, isomer decays,etc.) and nuclear reaction (three-bodyforces, nuclear symmetries, fissionand spallation mechanism, etc.) stud-ies. In additon, in-beam detector testsare foreseen. We are looking forwardfor collaboration!

PAWEL OLKO

IFJ PAN, Kraków

100 Years of Nuclear Physics: The Legacy of Ernest Rutherford

Just over two years ago, I wasinvited to address the New ZealandHigh Commission in London on thecentenary of Ernest Rutherford’sNobel Prize for chemistry in 1908. Itwas on that occasion that I met hisgreat granddaughter, Mary Fowler, aprofessor of geophysics at the Univer-sity of London, from whom I havesince picked up several insights aboutthe great man’s life and views. Thisyear, we celebrate what is for manyscientists a far more momentous anni-versary: the centenary of the publica-tion of Rutherford’s 1911 paper onthe atomic nucleus in the Philosophi-cal Magazine (vol. 21, p. 669).

I cannot of course do justice in thisshort article to his incredible legacy toscience that sprang from that land-mark paper. In any case, there is littledoubt in my mind that in terms of hisachievements, influence, leadership,and impact on science, I would rankRutherford as the greatest experimen-tal physicist of all time, and certainlythe greatest experimental scientist ofthe last century. And while we nuclear

physicists rightly celebrate this yearas the centenary of the paper thatlaunched our discipline, I would liketo use this opportunity to outline someof the many other key contributionsRutherford made to science.

He was born near Nelson, in NewZealand in 1871 and, after studying atCanterbury College in Christchurch,won a scholarship to come to Englandto work at JJ Thomson’s famousCavendish Laboratory in Cambridge.Initially, he joined “JJ” in the study ofthe newly discovered mysterious X-rays, but his attention was soon todrift to what would be his life-longpassion: radioactivity, also newly dis-covered and equally mysterious.

Radioactivity Rutherford’s early research was so

impressive that in 1898, when stillonly just 27 years old, he was offereda full professorship at McGill Univer-sity in Montreal, Canada. It was therethat he carried out the work that wonhim the Nobel Prize for a discovery

that would mark the end of chemis-try’s most cherished belief: that radio-activity was a process that couldtransform one element into another.Somehow, one type of atom emitted aparticle and became another type ofatom. No doubt mindful of the ill-repute arising from thousands of yearsof futile attempts to make gold fromlead, Rutherford is reported to havesaid to his collaborator FrederickSoddy: “Don’t call it transmutation,Soddy, or they’ll have our heads asalchemists!”

By 1904, he had become theworld’s leading expert on radioactiv-ity and had written the first ever text-book on the subject entitled, simply,Radio-activity. In it we find thefamous quote: “The phenomenaexhibited by the radioactive bodiesare extremely complicated and someform of theory is essential to connectin an intelligible manner the mass ofexperimental facts that have now beenaccumulated.”

Of course, Rutherford could nothave predicted the quantum revolution

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that took place in the first quarter ofthe 20th century. The book, which hededicated to JJ Thomson, describes allof his work at McGill with Soddy,including his coining of alpha andbeta radiation and the concept of thehalf-life (even if the term itself came afew years later). It was the 2nd editionof the book published in 1905 thatwould become the standard textbookon the subject, providing a completereview of what was known at thetime.

The Age of the Earth It was also in 1904 that Rutherford

finally fully understood how to esti-mate the age of the earth: that if theradioactive elements in the Earth’scrust, such as radium, thorium, actin-ium, and uranium, have been activesince our planet was formed then theirproportions now could tell us howlong they had been there. Rutherfordwould call on two different pieces ofevidence for this. First, he knew hecould measure the amount of heliumgas trapped in rocks. Since he wasconfident that his alpha particles werein fact ionized helium atoms, theamount of helium would tell him howlong the radioactive materials hadbeen decaying in the rocks and hencetheir age.

But the second method was theone that would capture the imagina-tion of the scientific community at thetime. The great 19th-century physicistand inventor, William Thompson(later Lord Kelvin) had worked outthe age of the earth many years earlierto be one or two orders of magnitudeyounger than the correct value, basedon a model in which it started off in amolten state and has been coolingever since. This figure worried geolo-gists (and biologists) who wanted afigure of many hundreds of millions

of years. However, taking intoaccount the heat given off by radioac-tive elements in the earth’s coremeant that it had to be much olderthan Kelvin’s estimate in order tohave cooled down to its current tem-perature. Rutherford delivered afamous lecture at the Royal Institutionin London in May 1905. Kelvin— bythis time the grand old man of Britishscience—was in the audience. Ruther-ford knew this and was nervous, forhe knew that it would not be a wisemove to publicly embarrass Kelvin byso dramatically revising his value forthe age of the earth. Luckily, itseemed Kelvin was asleep during thelecture. Then, at the crucial moment,Rutherford noticed that he had openedone eye. It was at this moment thatRutherford made his famously diplo-matic remark: “Kelvin had limited ageof earth provided no new sources ofheat found. That prophetic utterancereferred to what we are now consider-ing!” He would later say that, on hear-ing this, Kelvin “beamed” at him.

“Single Scattering” And so we come to the famous

alpha scattering experiment of 1909.Rutherford had moved from McGillto the University of Manchester in1907 and it was there that he oversawthe great experiment carried out byhis assistants, Hans Geiger and ErnestMarsden in 1909 in which a beam ofalpha particles from a radium sourcewere fired at a gold leaf. Theyobserved with amazement how one inevery eight thousand of these particle“bullets” bounced right back from thethin gold sheet. Of course, everyphysicist today knows the explana-tion, but it took Rutherford over ayear to work out what was happening.When he did, he published it in hispaper: “The scattering of alpha and

beta particles by matter and the struc-ture of the atom.” In it, he explainedthe existence of the tiny dense atomicnucleus by coming up with a scatter-ing formula—one that he worked outfrom the classical theory of electro-static deflection of charge, but whichcan be derived quantum mechani-cally too (using Born Approxima-tion). With this new model of theatom, Rutherford would overthrowthe old “plum pudding” model pro-posed by his mentor, J J Thomson.

And so nuclear science was born,and Rutherford replaced Thomson asthe dominant figure in British science.

Over half a century later, thesame reasoning that led Rutherfordto conclude the existence of the tinedense nucleus at the heart of theatom would point to the quark struc-ture of nucleons, this time via elec-tron scattering from hydrogen(protons) in what is referred to asdeep inelastic scattering.

I recall, as young research student,deriving what is known as theSchrödinger-equivalent Dirac equa-tion containing what is know as the“Darwin term” in the nuclear poten-tial. I did not know it at the time, butthis term is named after Charles Gal-ton Darwin (grandson of the greatDarwin) who worked under Ruther-ford in Manchester. The youngDarwin recalls an occasion around1910 while at dinner one eveningwhen Rutherford first talked about theidea of “single scattering” of the alphaparticles and how they trace a para-bolic path through the atom, muchlike the path of a comet passing closeby the sun’s gravitational field.Indeed, a copy of Newton’s Principiawas found on Rutherford’s deskaround this time opened to the pageon the inverse square law of gravityand the bending of trajectories by

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hyperbolas. And it was a source ofgreat satisfaction to Rutherford thathis classical formula proved to be cor-rect even when derived quantummechanically.

The First Nuclear Reaction By 1914, Rutherford’s team in

Manchester was looking at how alphaparticles scattered from light atoms,such as hydrogen. They realized thatthe hydrogen nuclei should be kickedforward by the heavier alphas.Around this time, Marsden hadnoticed an anomalous result in whichmany more hydrogen nuclei thanexpected were being produced inalpha scattering from a range of lighttargets. He wondered whether thiswas due to contamination in his radio-active source, or even if the sourcewas spitting out hydrogen as well ashelium nuclei. Of course, although weknow now that certain heavy nucleido indeed decay via proton emission,this was not what was happening here.In fact, what Marsden had done with-out realizing it was split the atom—this, in 1914! His experiment was thevery first artificial nuclear reaction14N(α,p)17O. On this occasion it tookRutherford not 18 months, but fouryears to figure out what was happen-ing. In between 1915 and 1919, whenRutherford published four landmarkpapers, what was happening slowlybecame clearer. In the last of his 1919papers, Rutherford wrote about hisown series of nuclear reaction experi-ments: “We must conclude that thenitrogen atom is disintegrated underthe intense forces developed in a closecollision with a swift alpha particle,and that the hydrogen atom which isliberated formed a constituent part ofthe nitrogen nucleus.”

It was also around this time thatRutherford made yet another

prophetic remark, which reflects justhow pivotal his thinking was on thosearound him. It is well known thatJames Chadwick discovered the neu-tron in 1932. However, it was Ruther-ford who first suggested its possibleexistence. In his Bakerian lecture atthe Royal Society in 1920 he writes of“. . . the possible the existence of anatom of mass nearly 2, carrying onecharge, which is to be regarded as anisotope of hydrogen.”

Here he is postulating the existenceof the deuteron (the study of whichwould provide the material for my ownPh.D.). He then deduces from this “...the possible existence of an atom ofmass 1, which has zero charge.”

He even coined the term neutronfor this particle.

Moonshine? Despite making an early statement

regarding the splitting of the atomicnucleus that “some fool in a laboratorymight blow up the universe unawares,”Rutherford was by the early 1930s dis-missive of the energy locked up withinit, saying “The energy produced by thebreaking down of the atom is a verypoor kind of thing. Anyone whoexpects a source of power from thetransformation of these atoms is talk-ing moonshine.”

However, around the time of thediscovery of the neutron in 1932 (andlong before the discovery of nuclearfission) he is also said to have spokenprivately to Maurice Hankey, Brit-ain’s “man of secrets,” who had beenSecretary of the Committee of Impe-rial Defence in World War I. Hankeysaid Rutherford told him that.. “theexperiments on nuclear transforma-tion which he was supervising in Cam-bridge . . . might one day turn out to beof great importance to the defence ofthe country. He did not quite know in

what way this would be so…but someinner sense, for which he apparentlyhad no scientific justification, . . .warned him that someone should . . .‘keep an eye on the matter.’”

Further evidence of his interest inthe possibility of atomic energycomes from Rutherford’s interest inFermi’s experiments in Rome withslow neutrons. In the last year of hislife, Bohr and Wheeler wrote theirseminal paper on the liquid dropmodel of the nucleus. After a lectureon this topic by Bohr, he was over-heard booming: “When Niels, if in anuclear reaction mass disappears,energy will appear and, ultimately,whatever its initial form, be degradedto heat. It might be used.”

Science Funding Rutherford’s main influence on

science funding and policy camethrough the DSIR (Department of Sci-entific and Industrial Research),which had been founded during theGreat War, in 1915. After WWI, theDSIR became the main body fundingBritish scientific research. Today ofcourse, it has been replaced by theU.K. Research Councils. Scientistsnow write grant proposals forresearch funding and forget that thiswas not always the way science hasbeen funded. Until less than a centuryago, it tended to be through privatebenefactors, universities, learnedsocieties or industry; but not govern-ment—not for basic research.

Rutherford began tapping theDSIR for funds around 1924. Hesecured a salary for Chadwick at theCavendish, of which he was now thedirector, for the post of deputy direc-tor to carry out administrative workthat would free up Rutherford formore research. He also successfullyapplied for £8000 worth of funding

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for equipment, thus marking thelaunch of his research in “Big Sci-ence,” the legacy of which we seetoday in projects from FAIR at GSIto the LHC at Cern. Rutherfordwould, late in life, become a verypowerful figure in U.K. politics, butnever ceased to devote his efforts tohelping secure funding for his

researchers and promote sciencearound the world.

Rutherford was a loud, straight-talking giant of a man who did notsuffer fools gladly. He would push hiscolleagues, assistants, and studentshard in the lab and would offerencouragement all the time. TheEnglish chemist, Henry Tizard, once

said of him: “He never consideredwhether he should be a grave man or amerry man, but just let inclination forthe time take its course.”

JIM AL-KHALILI

University of Surrey

The French–US Theory Institute for Physics with Exotic Nuclei

A new initiative in nuclear theoryhas been launched: the French-US The-ory Institute for Physics with ExoticNuclei (FUSTIPEN). The Institute isbased at GANIL, and is dedicated topromoting collaborative projectsbetween researchers in the United Statesand in France in the area of physics ofor with exotic nuclei, including nuclearstructure and reaction theory, nuclearastrophysics, and tests of the standardmodel rare isotopes.

The Institute was inaugurated witha two-day meeting 18–19 January,attended by about 80 participants(Figure 1). The first day was devotedto the broad picture of the research

underway on exotic nuclei. Perspec-tives on the projects planned andunderway were given by representa-tives of the major funding agencies,namely T. Hallman of the U.S. Depart-ment of Energy, F. Staley of the CEA/DSM, and J. Martino the FrenchCNRS/IN2P3. There were numerousexamples showing the importance ofinternational collaboration in the largeexperimental projects.

The second day was a workshophighlighting theoretical problems thatcould benefit from collaborativeefforts, as well as reporting on ongo-ing French-U.S. collaborations in thephysics of exotic nuclei. High on the

list of problems was the need toimprove on present implementationsof mean-field theory, because of itsrole as the foundation of nuclearstructure theory. In specific regions ofthe nuclear chart the interacting shellmodel is the most powerful spectros-copy tool available for theory. Theimplementations of this model at theintersection of structure and reactiontheory remain one of the major futurechallenges. There is also a great needfor better reaction theory to makequantitative interpretations of experi-ments. Besides these key areas, therewere many topics that were also pre-sented, ranging from shell structureevolution, isospin breaking, astro-physical reaction rates, to giant reso-nances and fission.

The FUSTIPEN Institute will oper-ate by funding visits of U.S.-basedscientists to GANIL to collaborate on aone-to-one basis with French-based sci-entists. The visits can also include staysat the home institutions of the French-based researcher. Funding for FUSTI-PEN is provided by the Office ofNuclear Physics of the U.S. Departmentof Energy while GANIL provides thelocal support. The French grant suppliesfunding for French physicists to visit

Figure 1. Inauguration of FUSTIPEN, 18–19 January 2011 in GANIL, Caen,France.

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GANIL to collaborate with U.S. visi-tors. While FUSTIPEN is dedicated tonuclear theory, collaborations betweentheorists and experimentalists are essen-tial for understanding and planning ofexperiments, and such activities areencouraged by the Institute. The presentfunding of FUSTIPEN permits the sup-port of about 10–15 collaborative visitsper year. More details about the Instituteand the application process can befound on its website: [email protected].

Numerous FUSTIPEN activities arealready on the books. On 3 February2011, the topical meeting “Neutron-Proton pair correlations in N~Z nuclei”was devoted to specific correlationeffects due to the isoscalar pairing. On 3March 2011, the topical meeting“Effective field theories for nuclearstructure studies” investigated currentissues posed by the many-body problemof nuclear structure to effective fieldtheories. Further activities, such as the

topical meeting on “Probing two-nucleon correlations in reactions,” andworkshops on “Open quantum systems”and “Theory of nuclear fission” areplanned later in this year.

G. BERTCH, S. GALES,W. NAZAREWICZ, AND

M. PLOSZAJCZAK

FUSTIPEN

calendar


June 13–17 München, Bavaria, Germany. XIV

International Conference on HadronSpectroscopy HADRON2011

http://hadron2011.de/

June 13–17 Stockholm, Sweden. Nordic Con-

ference on Nuclear Physics 2011 http://www.nuclear.kth.se/NCNP2011/

Home.html

June 17–20 Northampton, Massachusetts, USA.

NuSYM11 International Symposium onNuclear Symmetry Energy

http://www.smith.edu/nusym11/

June 27–July 2 Constanta, Romania. “Advanced

many-body and statistical methods inmesoscopic systems”

http://www.theory.nipne.ro/Constanta-Meso2011/

June 30–July 2 RIKEN, Wako, Saitama, Japan.

Joint International Symposium onFrontier of gamma-ray spectroscopy(gamma11)

http://www.cns.s.u-tokyo.ac.jp/gamma11/

July 4–10 St. Petersburg, Russia. Isomers in

Nuclear and InterdisciplinaryResearch Meeting (INIR-2011)

http://onlinereg.ru/inir2011

July 18–22 Quito, Ecuador. IX Latin Ameri-

can Symposium on Nuclear Physicsand Applications

http://www.lasnpa-quito2011.org/

August 8–12 Manchester, UK. Rutherford Cen-

tennial Conference on Nuclear Physics http://rutherford.iopconfs.org/

August 28–September 2 Guelph, Canada. Fourteenth

International Symposium on CaptureGamma-Ray Spectroscopy andRelated Topics

http://cgs14.physics.uoguelph.ca/

September 5–9 Vienna, Austria. International

Conference on Exotic Atoms andRelated Topics - EXA2011

http://www.oeaw.ac.at/smi/research/talks-events/exotic-atoms/exa-11/

September 11–18 Piaski, Poland. XXXII Mazurian

Lakes Conference on Physics http://www.mazurian.fuw.edu.pl/

September 16–24 Erice, Sicily, Italy. Erice School

2011 “From Quarks and Gluons toHadrons and Nuclei”

http://crunch.ikp.physik.tu-darmstadt.de/erice/

September 19–23 Prague, Czech Republic. Third

International Workshop on Com-pound-Nuclear Reactions andRelated Topics (CNR*11)

http://www-ucjf.troja.mff.cuni.cz/cnr11

October 9–14 Frascati, Italy. 8th International

Conference on Nuclear Physics atStorage Rings STORI’11

http://www.lnf.infn.it/conference/stori11/

October 11–15 Kyoto, Japan. Yukawa Interna-

tional Seminar “Frontier Issues inPhysics of Exotic Nuclei” (YKIS2011)

http://www2.yukawa.kyoto-u.ac.jp/~ykis2011/ykis/index.html

November 14–17 Wako, Japan. The 11th International

Symposium on Origin of Matter and

Evolution of Galaxies (OMEG11) http://www.cns.s.u-tokyo.ac.jp/omeg11

November 23–28 Hanoi, Vietnam. International

Symposium on Physics of UnstableNuclei 2011 (ISPUN11)

http://www.inst.gov.vn/ispun11/

November 24–25 Athens, Greece. Workshop on

“Thermonuclear Reaction Rates forAstrophysics Applications”

http://libra.inp.demokritos.gr/THERRAA/

2012 January 23–27

Bormio, Italy. 50th InternationalWinter Meeting on Nuclear Physics

http://www.bormiomeeting.com/

February 22–25 Bormio, Italy. 1st Topical Work-

shop on Modern Aspects in NuclearStructure “Advances in NuclearStructure with arrays including newscintillator detectors”

http://www.mi.infn.it/WSBormio-Milano2012/

March 26–29 Pisa, Italy. Direct Reactions with

Exotic Beams DREB2012http://dreb2012.df.unipi.it/Dreb/

WELCOME.html

May 28–June 2 St. Petersburg, Florida, USA.

Eleventh Conference on the Intersec-tions of Particle and Nuclear PhysicsCIPANP 2012

http://cipanp2012.triumf.ca/

September 17–21 Bucharest, Romania. European

Nuclear Physics Conference EuNPC2012

http://www.ifin.ro/eunpc2012/

More information available in the Calendar of Events on the NuPECC website: http://www.nupecc.org/

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