A Facility for Rare Isotope Beams

in the U.S.

Robert Tribble

Texas A&M University

June 6, 2007

A U.S. History Lesson

The Early Years

1989 Long Range Plan“Wholly new vistas would be opened by a radioactive nuclear beam (RNB) accelerator. Already, experiments with radioactive beams at the Bevalac facility have given evidence for neutron halos in neutron-rich nuclei, and provide tantalizing hints that nuclei with regions of nearly pure neutron matter can be produced. An RNB facility would also provide critical information for nuclear astrophysics, give access to entirely new nuclei even further from stability, and enable the investigation of novel phenomena such as massive isospin transfer, or of new forms of multiparticle radioactivity. Last but not least it may lead us closer to the long-sought superheavy island of nuclear stability.”

Evolution of an Idea

1996 Long Range Plan3. The scientific opportunities made available by

world-class radioactive beams are extremely compelling and merit very high priority. The U.S. is well-positioned for a leadership role in this important area; accordingly

• We strongly recommend the immediate upgrade of the MSU facility to provide intense beams of radioactive nuclei via fragmentation.• We strongly recommend development of a cost-effective plan for a next generation ISOL-type facility and its construction when RHIC construction is substantially complete.

The RIA Conceptdeveloped by

NSAC subcommittee – 1999Chair – H. Grunder

A Recommendation

2002 Long Range Plan2. The Rare Isotope Accelerator (RIA) is

our highest priority for major new construction. RIA will be the world-leading facility in nuclear structure and nuclear astrophysics

The exciting new scientific opportunities offered by research with rare isotopes are compelling. RIA is required to exploit these opportunities and to ensure world leadership in these areas of nuclear science. RIA will require significant funding above the nuclear physics base. This is essential so that our international leadership positions at CEBAF and at RHIC be maintained.

A Recommendation

2002 Long Range Plan2. The Rare Isotope Accelerator (RIA) is

our highest priority for major new construction. RIA will be the world-leading facility in nuclear structure and nuclear astrophysics

The exciting new scientific opportunities offered by research with rare isotopes are compelling. RIA is required to exploit these opportunities and to ensure world leadership in these areas of nuclear science. RIA will require significant funding above the nuclear physics base. This is essential so that our international leadership positions at CEBAF and at RHIC be maintained.

Next Steps• 2003 – RIA tied for #3 priority in DOE 20

year facility plan• 2005 – National Academy Study initiated to

assess science of RIA (RISAC)• 2006 – DOE Secretary Bodman says project

must be de-scoped and start delayed to 2011 –

Congressional testimony in February, 2006• New ‘charge’ given to RISAC• NSAC (FRIB) Task Force created• Call for a new U.S. Long Range Plan

NSAC Task Force

• NSAC charge – July, 2006

“. . . perform an evaluation of the scientific ‘reach’ and technical options for the development of a world-class facility in the United States for rare isotope studies with the funding envelope described below and in the context of existing and planned research capabilities world-wide.

In the context of the projected out-year budget for the Office of Science, funding is possible to start design and construction of a rare isotope beam facility that is up to half the cost of RIA (actual year dollars) early in the next decade. ”

Scientific Opportunities with a Rare-Scientific Opportunities with a Rare-Isotope Facility in the United StatesIsotope Facility in the United States

Final Report of the National AcademiesRare-Isotope Science Assessment Committee

08 December 2006

J. Ahearne (Sigma Xi, Duke Univ) and S. Freedman (UC Berkeley)

Report at FRIB Task Force meeting

Format of the committee’s Format of the committee’s analysisanalysis

• RISAC reviewed the potential scientific thrusts for a next-generation U.S.-based rare-isotope facility and identified the most compelling potential scientific advances– Discoveries in nuclear-structure science– Key insights into nuclear astrophysics– Sensitive tests of fundamental physics

• The committee also examined broader scientific and technological applications

• The committee reviewed worldwide efforts to place a U.S. initiative into a global context

• The committee concluded that rare-isotope science is a vital component of nuclear physics addressing fundamental issues of importance to physics in general

RISAC Report - Science Drivers

• Nuclear Structure– Explore the limits of existence and study new phenomena– Possibility of a broadly applicable model of nuclei– Probing neutron skins (study of neutron matter)– Synthesis of Superheavy elements

• Nuclear Astrophysics– The origin of the heavy elements– Explosive nucleosynthesis– Composition of neutron star crusts

• Fundamental Symmetries– Tests of fundamental symmetries with rare isotopes

• Other Scientific Applications– Stockpile stewardship, materials, medical, reactors

Take-home messageTake-home message• Nuclear structure and nuclear astrophysics constitute a vital

component of the nuclear science portfolio in the United States.– Study of rare isotopes contributes to uncovering the principles

governing the structure of all nuclei – Rare-isotope science contributes important data to nuclear

astrophysics, helping to explain the origins of the elements as well as the processes behind the most violent events in the Universe

– Availability of rare isotopes provides opportunities for making important discoveries about the fundamental symmetries of nature

• A U.S. facility for rare isotope beams would be complementary to existing and planned international efforts, particularly if based on a heavy-ion linear accelerator. With such a facility, the United States would be a partner among equals in the exploration of world-leading scientific thrusts.

• The science addressed by a rare isotope facility, most likely based on a heavy ion driver using a linear accelerator, should be a high priority for the United States.

FRIB

James Symons

Lawrence Berkeley National Laboratory

April 30, 2007

Task Force Findings• Beam Power is important parameter for isotope

production (energies > 150 MeV/A)• Linac costs scale with energy (not linear!)• If decrease the energy of the driver but maintain the

power, costs can be saved (lose multi-user capability)• Success of the RIA R&D Program

– Multi-charge state acceleration– Performance of VENUS ECR Ion Source

• ANL (AEBL)/MSU (ISF) have developed designs for

drivers with half the energy of RIA and twice the current

Recommendation

We have been asked to provide guidance on the scientific reach of technical options for a RIBfacility. We have done this, and details can be found in this report. Nevertheless, one of themstands out so strongly that we are making it the basis of our single recommendation.

We recommend that DOE and NSF proceed with solicitation of proposals for a FRIB basedon the 200 MeV, 400 kW superconducting heavy-ion driver linac at the earliest opportunity.This unique facility will have outstanding capabilities for reaccelerated beams, fast beams andstopped beams. It will be complementary to other facilities existing and planned, world-wide.

In conclusion, a facility for rare-isotope beam research as discussed above meets the requirementsset by the Agencies in their charge to NSAC. It will address the science identified by RISAC; thecost is substantially less than RIA; and the facility will, without doubt, be world-class. Twodecades have passed since the opportunities for rare-isotope research were first identified andother countries around the world are moving aggressively to exploit them. If the United States isto retain a leading role in this research area, there is no time to lose.

Enabling the Science

AEBL – ANL ISF – MSU

Two options based on superconducting HI linac

Cost estimates are comparable for two projects!

• Multiple charge state acceleration and transport• Stripper(s) to boost to high charge states

Both designs have:

C.K. Gelbke, December 7, 2006, Slide 19

ISF (NSCL Site Option)

C.K. Gelbke, December 7, 2006, Slide 20

ISF Plan view (South Campus Site)

Energy/nucleon: 200 MeV 238U, 222 MeV 129Xe, 376 MeV 3He, 525 MeV 1H– up to 400 kW beam power

The Advanced Exotic Beam Laboratory (AEBL) at ANL – 200 MeV/u, 400 kW

Color code:Black = existing facilityBlue+ green = AEBL baselineRed = Low-cost upgrade

A New Long Range Planfor U.S. Nuclear Science

• NSAC charged to develop new LRP by DOE

and NSF in July, 2006• Plan due by end of 2007• Meeting at Galveston during week of April 29

set recommendations• Four principle recommendations for report

Recommendations• We recommend completion of the 12 GeV Upgrade at Jefferson Lab. The Upgrade

will enable new insights into the structure of the nucleon, the transition between the hadronic and quark/gluon descriptions of nuclei, and the nature of confinement.

• We recommend construction of the Facility for Rare Isotope Beams, FRIB, a world-leading facility for the study of nuclear structure, reactions and astrophysics. Experiments with the new isotopes produced at FRIB will lead to a comprehensive description of nuclei, elucidate the origin of the elements in the cosmos, provide an understanding of matter in the crust of neutron stars, and establish the scientific foundation for innovative applications of nuclear science to society.

• We recommend a targeted program of experiments to investigate neutrino properties and fundamental symmetries. These experiments aim to discover the nature of the neutrino, yet unseen violations of time-reversal symmetry, and other key ingredients of the new standard model of fundamental interactions. Construction of a Deep Underground Science and Engineering Laboratory is vital to US leadership in core aspects of this initiative.

• The experiments at the Relativistic Heavy Ion Collider have discovered a new state of matter at extreme temperature and density—a quark-gluon plasma that exhibits unexpected, almost perfect liquid dynamical behavior. We recommend implementation of the RHIC II luminosity upgrade, together with detector improvements, to determine the properties of this new state of matter.

What’s Next?

• NSAC will consider Task Force report in July• If approved, NSAC will transmit report to DOE

and NSF• Expect DOE to develop a RFP soon• Call for Proposals – fall of 2007• [Project already endorsed in the new LRP]• Mechanism must be set up to choose proposal• Funding start in FY11 and completion around

FY17

On to ConstructionOn to Constructionaround INPC2010!around INPC2010!