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QNP04, Bloomington, May 24-28, 2004, 1
Operated by the Southeastern Universities Research Association for the U.S. Department Of Energy
Thomas Jefferson National Accelerator Facility
The Future of Hadronic Physics in the US
QNP04May 27, 2004BloomingtonKees de JagerJefferson Lab
• Introduction• RHIC-spin• JLab at 12 GeV• Electron-Ion Collider• Other Issues• Summary
QNP04, Bloomington, May 24-28, 2004, 2
Operated by the Southeastern Universities Research Association for the U.S. Department Of Energy
Thomas Jefferson National Accelerator Facility
What is Hadronic Physics?
What are the goals?• Understanding the structure of protons and neutrons in terms of quarks and
gluons• Understanding the structure of light nuclei in terms of nucleons at low energy
and of quarks and gluons at high energy• Linking the physics of nuclei to strong QCD
How do we reach those goals?• Measure form factors, structure functions and generalized parton distributions
to determine how the quarks and gluons are distributed inside the nucleons• Probe nucleons and nuclei with photons and electrons to produce excited
mesonic and baryonic states • High-energy proton-proton collisions provide a complimentary window into how
quarks and gluons build up nucleons• Lattice QCD calculations are expected to provide the best theoretical means to
compare experimental results with QCD
NSAC Report on Performance Measures (November 2003)
QNP04, Bloomington, May 24-28, 2004, 3
Operated by the Southeastern Universities Research Association for the U.S. Department Of Energy
Thomas Jefferson National Accelerator Facility
RHIC-spin: Non-pQCD Spin Structure from Hard Scattering RHIC-spin: Non-pQCD Spin Structure from Hard Scattering
1) Does preferential spin orientation of gluons account for a major portion of the “nucleon spin puzzle”?◊ Either answer interesting! If not gluon spins, then Lorbital !
2) Do sea antiquarks have a substantial and flavor-dependent helicity preference in a polarized nucleon?◊ Illuminates the relative roles of gluon splitting vs. pseudoscalar
meson clouds in generating the “sea”3) Unravel the contributions to transverse spin asymmetries (an area of
intense recent theoretical development) from: a) quark transverse spin preferences in a transversely polarized proton
(p)◊ “transversity” quark property decoupled from gluons
b) quark transverse motion preferences in p
◊ spin-kT correlation related to quark orbital angular momentum c) explicit chiral symmetry breaking from mq terms in LQCD
QNP04, Bloomington, May 24-28, 2004, 4
Operated by the Southeastern Universities Research Association for the U.S. Department Of Energy
Thomas Jefferson National Accelerator Facility
Absolute Polarimeter (H jet)
Strong AGS Snake
Equip-ment to
be installed
after FY03
The RHIC Spin FacilitiesThe RHIC Spin Facilities First polarized collider, exploits Siberian Snake technology
Enables p + p pol’n measurements in s and pT regime where low-order pQCD is applicable
Provides access to nucleon spin structure info complementary to polarized DIS
Major experimental efforts at STAR, PHENIX and PP2PP
Virgin territory + new technology signifi-cant challenges + steep learning curve
QNP04, Bloomington, May 24-28, 2004, 5
Operated by the Southeastern Universities Research Association for the U.S. Department Of Energy
Thomas Jefferson National Accelerator Facility
RHIC-spin TimelineRHIC-spin Timeline
First p + p collisions in 1/02: 200 GeV, Pbeam ~ 15% (vert. spin only), L ~ 5 x 1029, L dt ~ 300 nb-1 see polarization survival, first transverse spin results
Second run 5/03: 200 GeV, Pbeam ~ 30% (vert. + longitudinal), L ~ 2 x 1030, L dt ~ 800 nb-1 commission rotators, first ALL measurements
2004-5: commissioning of new AGS snakes to improve Pbeam; absolute Pbeam calibration exp’t; first measurements of g via ALL for abundant probes (jets, 0’s with ~ 5 pb1); measure transverse single-spin asymmetry for not-quite-back-to-back dijets for kT sensitivity.
2006-10: “Rare” processes to map g(x) fully: Detect -jet coincidences in polarized proton collisions at s = 200 and 500 GeV
Measure two-spin asymmetry in production rates between equal vs. opposite helicities, as function of (jet), (), pT ( )
Assuming two-body parton kinematics, can infer initial x values of gluon and quark
2009-12: W Production-> Direct determination of u/u and d/d:Measure single-spin parity-violating asym. AL for p + p W + X with respect to helicity flip of each beam. Requires 500 GeV, upgraded forward tracking, and as much P2L dt as we can get!
- -
QNP04, Bloomington, May 24-28, 2004, 6
Operated by the Southeastern Universities Research Association for the U.S. Department Of Energy
Thomas Jefferson National Accelerator Facility
CEBAF @ 6 GeV, Present and Future
• How are nucleons made from quarks and gluons? Nucleon (electro-magnetic and -weak) form factors, separate u, d
and s Nucleon excitation spectrum, new resonances (pentaquark)
Spin structure functions in valence region Generalized Parton Distributions, mainly DVCS
• How does QCD work in the strong (confinement) region Pion form factor
• How does the NN force arise from the partonic structure of hadronic matter?
Medium modifications Color transparancy
• What is the Structure of Nuclear Matter? High-resolution (~300 keV) hypernuclear spectroscopy (1p-shell) Proton knock-out (2H, 3,4He, 16O, …)
• At what scale does the partonic structure of nuclear matter become apparent?
Few-body form factors, deuteron photodisintegration
• Standard Model Tests Q-weak
QNP04, Bloomington, May 24-28, 2004, 7
Operated by the Southeastern Universities Research Association for the U.S. Department Of Energy
Thomas Jefferson National Accelerator Facility
CEBAF @ 12 GeV, WHY?
• Gluonic Excitations and the Origin of Confinement
• Developing a Unified Description of Hadron Structure The Generalized Parton Distributions (GPDs) as Accessed via
Deep(ly) Exclusive Reactions Valence Quark Structure and Parton Distributions Form Factors – Constraints on the GPDs
Other Topics in Hadron Structure
• The Physics of Nuclei The Short-Range Behavior of the N-N Interaction and Its QCD
Basis Identifying and Exploring the Transition from the Nucleon/Meson
Description of Nuclei to the Underlying Quark/Gluon Description
• Symmetry Tests in Nuclear Physics Standard Model Tests
QNP04, Bloomington, May 24-28, 2004, 8
Operated by the Southeastern Universities Research Association for the U.S. Department Of Energy
Thomas Jefferson National Accelerator Facility
Gluonic Excitations and the Origin of ConfinementTheoretical studies of QCD suggest that confinement is due to the formation of “Flux tubes” arising from the self-interaction of the glue, leading to a linear potential (and therefore a constant force)
Flux
tube
forms
between
linear potential
From G. Bali
Experimentally, we want to “pluck” the flux tube and see how it
responds
QNP04, Bloomington, May 24-28, 2004, 9
Operated by the Southeastern Universities Research Association for the U.S. Department Of Energy
Thomas Jefferson National Accelerator Facility
First excited state of flux tube has J=1 combined with S=1 for quarks
Photons couple to exotic mesons via VM transition (same spin configuration)
Photons Preferred for Flux Tube Excitations
JPC = 0-+ 0+- 1+- 1-+ 2-+ 2+-
exotic (mass ~ 1.7 – 2.3 GeV)
LSS12S = S + S12J = L + SC = (-1)L + SP = (-1)L + 1
Normal mesons: JPC = 0-+ 1+- 2-+
Double-blind Monte Carlo simulation: 2 % exotic signal clearly visible
QNP04, Bloomington, May 24-28, 2004, 10
Operated by the Southeastern Universities Research Association for the U.S. Department Of Energy
Thomas Jefferson National Accelerator Facility
• Use photons to produce meson final states– tagged photon beam with 8 – 9 GeV– linear polarization to constrain production mechanism
• Use large acceptance detector– hermetic coverage for charged and neutral particles– typical hadronic final states: f1 KK KK
b1
– high data-acquisition rate
• Perform partial-wave analysis– identify quantum numbers as a function of mass– check consistency of results in different decay modes
Strategy for Exotic Meson Search
QNP04, Bloomington, May 24-28, 2004, 11
Operated by the Southeastern Universities Research Association for the U.S. Department Of Energy
Thomas Jefferson National Accelerator Facility
GPDs: A Unified Description of Hadron Structure
GPDs
Transverse momentum of partons
Quark spin distributions
Form factors
Quark momentum distributions
Pion cloud
Pion distribution amplitudes
Quark angular momentum
QNP04, Bloomington, May 24-28, 2004, 12
Operated by the Southeastern Universities Research Association for the U.S. Department Of Energy
Thomas Jefferson National Accelerator Facility
DVCS SSA Measures phase and amplitude directlyDVCS at 11 GeV can cleanly test correlations in nucleon structure(data shown – 2000 hours in CLAS++)
DVCS and Bethe-Heitler are coherent can measure amplitude AND phase
QNP04, Bloomington, May 24-28, 2004, 13
Operated by the Southeastern Universities Research Association for the U.S. Department Of Energy
Thomas Jefferson National Accelerator Facility
Measuring the GPDs
•Key experimental capabilities include:– CW (100% duty factor) electron beams
(permits fully exclusive reactions)– modern detectors
(permit exclusive reactions at high luminosity)– adequate energy
(~10 GeV to access the valence quark regime)
Measurements of GPDs through many reaction channelsCLAS++ and calorimeter+MAD in Hall ADVCS on proton and neutron, DVMP, RCS, nucleon EMFF
QNP04, Bloomington, May 24-28, 2004, 14
Operated by the Southeastern Universities Research Association for the U.S. Department Of Energy
Thomas Jefferson National Accelerator Facility
Extending DIS to High x with A1n
12 GeV will access the valence quark regime (x > 0.4), where constituent quark properties are not masked by the sea quarks
QNP04, Bloomington, May 24-28, 2004, 15
Operated by the Southeastern Universities Research Association for the U.S. Department Of Energy
Thomas Jefferson National Accelerator Facility
Transition from ‘Strong’ to pQCD
€
fπ (Q2) =12 fπ
2πCFα s(Q2)
Q2
•Simplest valence quark structure
•pQCD is expected to manifest at low momentum transfer
•pQCD and non-pQCD calculations exist
•The asymptotic pion form factor:
Pion Elastic Form FactorElectroproduction -/+ Ratio in 4He
QNP04, Bloomington, May 24-28, 2004, 16
Operated by the Southeastern Universities Research Association for the U.S. Department Of Energy
Thomas Jefferson National Accelerator Facility
JLab tests of the Standard Model • Measurements of sin2(W) below MZ
provide strict tests of the SM• Measurements in different systems
provide complementary information• Møller Parity Violation can be measured
at JLab even more accurately than in E158
• DIS-Parity violation measurement is easily carried out at JLab
RPVRPV
No SUSY No SUSY dark matterdark matter
hep-ph/0205183
Weak Mixing Angle MS-bar schemeJens Erler
QNP04, Bloomington, May 24-28, 2004, 17
Operated by the Southeastern Universities Research Association for the U.S. Department Of Energy
Thomas Jefferson National Accelerator Facility
CEBAF @ Higher Energies How?
• Design choices for CEBAF’s construction make tripling the original energy to 12 GeV remarkably cost effective
• The extraordinary performance of the original SRF cavities has already brought us to 6 GeV, and further advances in SRF make 12 GeV straightforward
• Much of the existing experimental equipment can be upgraded for use at higher energies, minimizing equipment costs
QNP04, Bloomington, May 24-28, 2004, 18
Operated by the Southeastern Universities Research Association for the U.S. Department Of Energy
Thomas Jefferson National Accelerator Facility
CHL-2CHL-2
Upgrade magnets Upgrade magnets and power and power suppliessupplies
Enhance equipment in Enhance equipment in existing hallsexisting halls
6 GeV CEBAF1112Add new hallAdd new hall
QNP04, Bloomington, May 24-28, 2004, 19
Operated by the Southeastern Universities Research Association for the U.S. Department Of Energy
Thomas Jefferson National Accelerator Facility
Hall A: MAD and the HRS
MAD Design PropertiesMomentum Range 0.4 - 8.6 GeV/cMomentum Acceptance ± 15%Momentum Resolution 0.1%Scattering Angle Range 5° - 150°Angular Acceptance 5 - 28 msrAngular Resolution
horizontal 1 mradvertical 1 mrad
Target Length Acceptance 50 cmVertex Resolution 0.5 cme/h discrimination 50000:1 (98%)π/K discrimination 1000:1 (95%)Maximum DAQ Rate 20 kHz
Medium Acceptance Detector (MAD) at high luminosity and large acceptance
QNP04, Bloomington, May 24-28, 2004, 20
Operated by the Southeastern Universities Research Association for the U.S. Department Of Energy
Thomas Jefferson National Accelerator Facility
Hall B: CLAS++
CLAS upgraded to higher (1035) luminosity and coverage
Angular coverageForward 5° - 37°Central 40° - 135°
Track resolutionmomentum 0.001p 1 mrad 1 mrad
QNP04, Bloomington, May 24-28, 2004, 21
Operated by the Southeastern Universities Research Association for the U.S. Department Of Energy
Thomas Jefferson National Accelerator Facility
Hall C: HMS and SHMS
Central Momentum 2.5 - 11 GeV/cMomentum Acceptance -15 - +25%Momentum Resolution 0.2%Scattering Angle Range 5.5° - 25°Angular Acceptance 2 - 4 msr
horizontal ± 18 mradvertical ± 50 mrad
Angular Resolutionhorizontal 2 mradvertical 1 mrad
Target Length Acceptance 50 cmVertex Resolution 0.2 cme/h discrimination 1000:1 (98%)π/K discrimination 100:1 (95%)
Super High Momentum Spectrometer (SHMS) at high luminosity and forward angles
QNP04, Bloomington, May 24-28, 2004, 22
Operated by the Southeastern Universities Research Association for the U.S. Department Of Energy
Thomas Jefferson National Accelerator Facility
Hall D: The GlueX Detector
Photon Flux 108 /sCharged Particles
coverage 1° - 170°momentum reso 1 - 2%position reso 150 µmvertex reso 500 µm
Photonsenergy measured 1° - 120°Pb glass reso 2 + 5%/√Ebarrel reso 4.4%/√E
Trigger level 1 rate 20 kHz
Coherent bremsstrahlung
QNP04, Bloomington, May 24-28, 2004, 23
Operated by the Southeastern Universities Research Association for the U.S. Department Of Energy
Thomas Jefferson National Accelerator Facility
Status of 12 GeV Upgrade
• JLab upgrade is relatively modest project (175 - 250 M$)
• CD-0 was approved on April 1, 2004
• JLab is looking for 25+ M$ non-DOE fundingWithin a year JLab will present a CDR for review to CD-1
• The goal is to complete the upgrade early in the next decade
QNP04, Bloomington, May 24-28, 2004, 24
Operated by the Southeastern Universities Research Association for the U.S. Department Of Energy
Thomas Jefferson National Accelerator Facility
Why Electron-Ion Collider?
•Polarized DIS and e-A physics: in past only in fixed target mode
•Collider geometry--> distinct advantages (HERA Experience)
•Better angular resolution between beam and target fragments- Better separation of electromagnetic probe- Recognition of rapidity gap events (recent diffractive physics)- Better measurement of nuclear fragments
•Higher Center of Mass energies reachable
•Tricky issues: integration of interaction region and detector
QNP04, Bloomington, May 24-28, 2004, 25
Operated by the Southeastern Universities Research Association for the U.S. Department Of Energy
Thomas Jefferson National Accelerator Facility
Deep Inelastic Scattering
•Observe scattered electron [1] inclusive measurement
•Observe [1] + current jet [2] semi-inclusive measurement
•Observe [1] + [2] + remnant jet [3] exclusive measurement
•Luminosity requirements goes up as we go from [1] --> [2] --> [3]
•Exclusive measurements also puts demanding requirement on integration of detectors and interaction region
[3]
[2]
[1]
QNP04, Bloomington, May 24-28, 2004, 26
Operated by the Southeastern Universities Research Association for the U.S. Department Of Energy
Thomas Jefferson National Accelerator Facility
Scientific Frontiers Open to EICs
•Nucleon structure, role of quarks and gluons in the nucleons- Unpolarized quark and gluon distributions, confinement in
nucleons- Polarized quark and gluon distributions - Correlations between partons
•Exclusive processes--> Generalized Parton Distributions- Understanding confinement with low x/lowQ2 measurements
•Meson Structure:- Goldstone bosons and play a fundamental role in QCD
•Nuclear Structure, role of partons in nuclei- Confinement in nuclei through comparison e-p/e-A scattering
•Hadronization in nucleons and nuclei & effect of nuclear media
- How do knocked off partons evolve in to colorless hadrons
•Partonic matter under extreme conditions- For various A, compare e-p/e-A
QNP04, Bloomington, May 24-28, 2004, 27
Operated by the Southeastern Universities Research Association for the U.S. Department Of Energy
Thomas Jefferson National Accelerator Facility
Unpolarized e-p at EIC
•Although large kinematic region already covered at HERA, additional studies with high luminosities desirable
•Unique features: high luminosity, variable CM energy, He beams, and improved detectors and interaction regions
•Precision Measurements:- With d, He beams: neutron structure - The evolution of the strong coupling constant- Photo-production physics at high energies - Gluon distribution - FL structure function - Slope of F2 structure function to explore confinement - Diffractive physics - Semi-inclusive and exclusive reactions - Nuclear fragmentation region
[1][1][1][1][1][1][1][1,2][2,3]
QNP04, Bloomington, May 24-28, 2004, 28
Operated by the Southeastern Universities Research Association for the U.S. Department Of Energy
Thomas Jefferson National Accelerator Facility
Polarized DIS at EIC
•Spin structure functions g1 (p,n) at low x, high precision
- g1(p-n): Bjorken Spin sum rule to better than 1% accuracy
•Polarized gluon distribution function G(x,Q2)- at least three different experimental methods
•Precision measurement of S(Q2) from g1 scaling violations
•Polarized s.f. of the photon from photo-production
•Electroweak s. f. g5 via W+/- production
•Flavor separation of PDFs through semi-inclusive DIS
•Deeply Virtual Compton Scattering (DVCS)- Generalized Parton Distributions (GPDs)
•Transversity
•Drell-Hern-Gerasimov spin sum rule test at high
•Target/Current fragmentation studies
•… etc….
[1]
[1]
[1][1][1,2][1][1,2][3][1][1][2,3]
QNP04, Bloomington, May 24-28, 2004, 29
Operated by the Southeastern Universities Research Association for the U.S. Department Of Energy
Thomas Jefferson National Accelerator Facility
Proton Spin Structure at Low x
eRHIC 250 x 10 GeV
Luminosity = ~85 inv. pb/day Fixed target experiments1989 – 1999 Data
10 days of EIC runAssume: 70% Machine Eff. 70% Detector Eff.
Studies included statistical error & detector smearing to confirm that asymmetries are measurable. No present or future approved
experiment will be able to make this measurement
QNP04, Bloomington, May 24-28, 2004, 30
Operated by the Southeastern Universities Research Association for the U.S. Department Of Energy
Thomas Jefferson National Accelerator Facility
Spin Structure of Neutron at Low x
•With polarized 3He
•~ 2 weeks of data at EIC
•Compared with SMC(past) & possible HERA data
•If combined with g1 of proton results in Bjorken sum rule
test to better than 1-2% within a couple of months of running
eRHIC 1 inv.fb
QNP04, Bloomington, May 24-28, 2004, 31
Operated by the Southeastern Universities Research Association for the U.S. Department Of Energy
Thomas Jefferson National Accelerator Facility
Photon Gluon FusionPhoton Gluon Fusion
•“Direct” determination of G- Di-Jet events: (2+1)-jet
events- High pT hadrons
•High √s at EIC - no theoretical ambiguities
regarding interpretation of data
•Both methods tried at HERA in un-polarized gluon determination & both are successful!
- NLO calculations exist- H1 and ZEUS results- Consistent with scaling
violation F2 results on G
Signal: PGF
BackgroundQCD Compton
QNP04, Bloomington, May 24-28, 2004, 32
Operated by the Southeastern Universities Research Association for the U.S. Department Of Energy
Thomas Jefferson National Accelerator Facility
Di-Jet at EIC vs. World Data for Di-Jet at EIC vs. World Data for G/GG/G
Good precisionClean measurement in x
range 0.01 < x < 0.3Constrains shape of G(x)Polarization in HERA much
more difficult than RHIC
eRHIC Di-Jet DATA 2fb-1
G from scaling violations > xmin~ 10-4 at eRHIC > xmin~ 3.10-4 at ELIC
ELIC
QNP04, Bloomington, May 24-28, 2004, 33
Operated by the Southeastern Universities Research Association for the U.S. Department Of Energy
Thomas Jefferson National Accelerator Facility
DVCS/Vector Meson ProductionDVCS/Vector Meson Production
•Hard Exclusive DIS process
• (default) but also vector mesons possible
•Remove a parton & put another back in!
Microsurgery of Baryons!
Access to skewed or off-forward PDFsPolarized structure: Access to quark orbital angular momentum
QNP04, Bloomington, May 24-28, 2004, 34
Operated by the Southeastern Universities Research Association for the U.S. Department Of Energy
Thomas Jefferson National Accelerator Facility
A Color Glass Condensate?
•At small x, partons are rapidly fluctuating gluons interacting weakly with each other, but still strongly coupled to the high x parton color charges which act as random static sources of COLOR charge
Analogous to spin GLASS systems in condensed matter: a disordered spin state coupled to random magnetic impurities•Gluon occupation number large; being bosons they can occupy the
same state to form a CONDENSATE Bose-Einstein condensate leads to a huge overpopulation of
ground states•A new “state matter”(??): Color Glass Condensate (CGC) at high energy density would display dramatically different, yet simple properties of glassy condensates•Experimental measurements: Gluon distributions inclusive semi-inclusive methods, specific predictions regarding enhancement of diffractive processes in e-A vs. e-p at identical (x,Q2), measurement of FL to access gluon distribution in nuclei•An e-A collider/detector experiment with high luminosity and capability to have different species of nuclei in the same detector would be ideal… Low x --> Need EIC
QNP04, Bloomington, May 24-28, 2004, 35
Operated by the Southeastern Universities Research Association for the U.S. Department Of Energy
Thomas Jefferson National Accelerator Facility
The eRHIC Ring-Ring Lay Out & Plans
•Full energy injection
•Polarized e- source & unpolarized e+ --> (polarization via synchrotron radiation)
•10 GeV main design but up to 5 GeV reduction possible with minimal polarization loss
•Fill in bunch spacing 35ns
QuickTime™ and aTIFF (LZW) decompressor
are needed to see this picture.
Present conservative estimates Lep ~ 4 x 1032 cm-2 sec-1 work on luminosity enhancement continues. Advantages: both positrons and electrons Disadvantages: No multiple detectors or/and Interaction Regions?
QNP04, Bloomington, May 24-28, 2004, 36
Operated by the Southeastern Universities Research Association for the U.S. Department Of Energy
Thomas Jefferson National Accelerator Facility
eRHIC: Linac-Ring Option
Features:
•Lep up to ~1034 cm-2sec -1
•Polarization transparency at all energies
•Multiple IRs and detectors- Long element free
regions
•STAR & PHENIX still run
•Full range of CM Energies
•Future upgrades to 20 GeV seem straightforward
Limitations:Positron beams not
possiblePhysics implications?
QuickTime™ and aTIFF (LZW) decompressor
are needed to see this picture.
QNP04, Bloomington, May 24-28, 2004, 37
Operated by the Southeastern Universities Research Association for the U.S. Department Of Energy
Thomas Jefferson National Accelerator Facility
ELIC Layout
One accelerating & one decelerating pass through a 7 GeV/pass CEBAF
Max CoM energy √s 65 GeV Max luminosity 8.1034 cm-2s-1 Polarized ions p, d, 3He Unpolarized ions up till 40Ca
QNP04, Bloomington, May 24-28, 2004, 38
Operated by the Southeastern Universities Research Association for the U.S. Department Of Energy
Thomas Jefferson National Accelerator Facility
A Detector for EIC A 4 Detector
•Scattered electrons to measure kinematics of DIS
•Scattered electrons at small (~0°) to tag photo production
•Central hadronic final state for kinematics, jet measurements, quark flavor tagging, fragmentation studies, particle ID
•Central hard photon and particle/vector detection (DVCS)
•~Zero angle photon measurement to control radiative corrections and in e-A physics to tag nuclear de-excitations
•Missing ET for neutrino final states (W decays)
•Forward tagging for 1) nuclear fragments, 2) diffractive physics
•At least one second detector should be incorporated… if not more
•EIC will provide: 1) Variable beam energies 2) different hadronic species, some of them polarized 3) high luminosity
QNP04, Bloomington, May 24-28, 2004, 39
Operated by the Southeastern Universities Research Association for the U.S. Department Of Energy
Thomas Jefferson National Accelerator Facility
Where do electrons and quarks go?
pq,e
10 GeV x 250 GeV1770 1600
scattered electron scattered quark
10 GeV
5 GeV900
5 GeV
100
QNP04, Bloomington, May 24-28, 2004, 40
Operated by the Southeastern Universities Research Association for the U.S. Department Of Energy
Thomas Jefferson National Accelerator Facility
Detector Design: HERA like…+ PID
AEROGEL
HCAL
p/Ae
EMCal
TOF
Outer trackers
Innertrackers
Beam elements
Solenoid
A HERA likeDetector with dedicated PID:>>Time of flight>>Aerogel Ckov
5 m
(Not to scale)
Forward detectors including
Roman Pots etc…
AND
QNP04, Bloomington, May 24-28, 2004, 41
Operated by the Southeastern Universities Research Association for the U.S. Department Of Energy
Thomas Jefferson National Accelerator Facility
eRHIC/ELIC Status & Design Ideas
•2001 LRP: NSAC enthusiastically supported R&D and stated its would be the next major for nuclear physics (after 12 GeV JLab upgrade)
•2003 NSAC committee on facilities’ high recommendation- Level 1 for physics, and level 2(eRHIC)/3(ELIC) for readiness
•ZDR (Zero Design Report) for eRHIC: Ring-Ring design - Identify R&D topics toward significant luminosity enhancement
•ELIC analysis and simulations:- electron cooling and short bunches- beam-beam physics- energy recovery linac physics
•Development on both projects will continue until the time to make the decisions to freeze technology and design options
QNP04, Bloomington, May 24-28, 2004, 42
Operated by the Southeastern Universities Research Association for the U.S. Department Of Energy
Thomas Jefferson National Accelerator Facility
The case for hadronic beams
•Goals of the baryon physics program:- Determine relevant degrees of freedom in baryons, and the
nature of their short-range interactions- Find “missing” conventional qqq excitations and identify new
kinds of states pentaquarks, hybrids, baryon-meson quasi-bound states
•To meet baryon physics goals we require:- High precise data using electromagnetic beams in new
channels: underway at JLab and other facilities You could get lucky and find an isolated missing
resonance near a new channel’s threshold Recent experience has shown: adding a new resonance
has consequences in several channels, convincing evidence will come from a simultaneous fit
- Polarization experiments: beam, target, recoil: E.g. all three possible, and planned, in
QNP04, Bloomington, May 24-28, 2004, 43
Operated by the Southeastern Universities Research Association for the U.S. Department Of Energy
Thomas Jefferson National Accelerator Facility
The case for hadronic beams…
• Hadron beams!
- Hadron-beam information complementary to that of photoproduction
- Simultaneous unitary analysis of data from N and N required to find new N*, * states
- Kaon-beam experiments could map out spectrum of a persistent + and its partners Would make enormous improvement in our
understanding of , and resonances• No plans for such beams at GSI or JPARC
- Is this something the US nuclear/hadron physics community should plan for the future?
QNP04, Bloomington, May 24-28, 2004, 44
Operated by the Southeastern Universities Research Association for the U.S. Department Of Energy
Thomas Jefferson National Accelerator Facility
SciDAC Initiative for Lattice QCD
•DOE Scientific Discovery through Advanced Computing Initiative: develop software/hardware infrastructure for next generation computers
•U.S. Lattice QCD Collaboration consists of 64 senior scientists. Research closely coupled to DOE’s experimental program:
- Weak Decays of Strongly Interacting Particles: BaBar (SLAC), B-Tevatron (FNAL), CLEO-c (Cornell)
- Quark-Gluon Plasma: RHIC (BNL)- Structure and Interactions of Hadrons: Bates, BNL, FNAL, JLAB,
SLACSciDAC Project:
•$6M, 30% JLab, 30% FNAL, 15% BNL, 25% universities- Unify software development and porting efforts for diverse
hardware platforms- Hardware prototyping efforts: clusters, QCDOC- No direct physics support
•Hope for significant funding for QCDOC-type machine in FY04/FY05
•Proposal for corresponding LGT funding at JLAB from FY06
QNP04, Bloomington, May 24-28, 2004, 45
Operated by the Southeastern Universities Research Association for the U.S. Department Of Energy
Thomas Jefferson National Accelerator Facility
LQCD Roadmap at Jefferson Lab
10-2
1990 2000 2010
Lattice gauge theory invented
First numerical simulations
Moments of GPD’s, N->
GPD measurements shown at JLAB
First data from CEBAF @12 GeV
100
10-1
10-4
10-6
1974
Lattice Spectrum agrees with Experiment for Conventional Mesons.
101
102
10-3
10-5
Flux tubes between Heavy Quarks
Current Clusters 0.3 Teraflops
FY05-06 Clusters ~5 Teraflops
Low moments, quenchedresonances
Precise moments,decay widths
QNP04, Bloomington, May 24-28, 2004, 46
Operated by the Southeastern Universities Research Association for the U.S. Department Of Energy
Thomas Jefferson National Accelerator Facility
The DOE-OSc “20-year plan” includes
the JLab 12 GeV Upgrade in its near-term (<7 year) prospects and eRHIC in its far-term (>14 year) prospects
QNP04, Bloomington, May 24-28, 2004, 47
Operated by the Southeastern Universities Research Association for the U.S. Department Of Energy
Thomas Jefferson National Accelerator Facility
CEBAF Upgrade
EIC
QNP04, Bloomington, May 24-28, 2004, 48
Operated by the Southeastern Universities Research Association for the U.S. Department Of Energy
Thomas Jefferson National Accelerator Facility
Summary
• Broad active program in hadronic physics (JLab@6GeV, RHIC-spin)
• Many important questions remain to be answered in detail (OAM, transversity, hadronization, gluonic structure,……)
• Confident that JLab@12GeV will happen, but need to keep pressure on DOE
• Vibrant and active community essential for future funding
• Excellent scientific case for Electron-Ion Collider
• Next NSAC Long Range Plan (starting ~2005) will probably be asked to evaluate need and options for electron-ion collider
• However, funding outlook at present not optimistic