Advanced Exotic Beam Laboratory (AEBL)

Don Geesaman

May 2007

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The Need for Exotic/Radioactive Isotopes Continued advances in nuclear

experiment, nuclear theory and in astrophysics reinforce the science case for exotic beams.

– advanced simulations.

– new experimental techniques, including ion and atom traps.

– new observations. We know nuclei far from the valley of

stability are different than their more familiar, stable cousins, but there are serious competing ideas of why this is so.

These exotic isotopes are key to exploring the grand scale behavior of the cosmos, including the origin of the heavy elements and the nature of stellar explosions.

The bounty of isotopes produced by an advanced facility holds great potential for applications in science and technology.

Manpower trained in the techniques of exotic isotopes is critical for our nation’s workforce.

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Significant Events in the Evolution of the Nation’s Plans for a Facility for Rare Isotope Beams

2005: National Academy Committee (RISAC) asked to evaluate Rare Isotope Science in the international context (GSI/FAIR and RIKEN/RIBF).

February 2006: Secretary Bodman states DOE support for the construction of a U.S. exotic beam facility for about half the cost of RIA with unique capabilities.

March 2006: Argonne presents plans for the Advanced Exotic Beam Laboratory to RISAC, satisfying the goal of a world-class facility at about half the price of RIA.

April 2006: Argonne presents plans for AEBL to ATLAS Users at ATLAS Users meeting.

July 2006: Nuclear Science Advisory Committee (NSAC) asked to: 1. evaluate technical concepts for such a facility and 2. to update Long Range Plan for Nuclear Science.

Dec 2006: RISAC gives such a facility, the Facility for Rare Isotope Beams (FRIB) strong endorsement.

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Conclusions of RISAC report

Nuclear structure and nuclear astrophysics constitute a vital component of the nuclear science portfolio in the United States.

Failure to pursue a U.S.-FRIB would likely lead to a forfeiture of U.S. leadership in nuclear-structure-related physics and would curtail the training of future U.S. nuclear scientists.

A U.S. facility for rare-isotope beams of the kind described to the committee 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 the world-leading scientific thrusts listed above.

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. The facility for rare-isotope beams envisaged for the United States would provide capabilities unmatched elsewhere that would help to provide answers to the key science topics outlined above.

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Significant Events in the Evolution of the Nation’s Plans for a Facility for Rare Isotope Beams

Dec 2006: Argonne and MSU present technical concepts to NSAC for Facility for Radioactive Ion Beams. MSU widely distributes proposal for a $650M facility.

March 2007: Ray Orbach states a facility for rare isotope beams is in the plan DOE is presenting to Congress for its future facilities.

May 2007 NSAC Rare Isotope Beams Task Force releases draft report to Long Range Plan Working Group Committee enthusiastically endorsing 200 MeV/u heavy ion driver for rare isotope beams.

May 2007: NSAC Long Range Working Group reaffirms exotic beam Facility as highest priority for new construction (see slide 6).

Expected future schedule: Summer 2007: A new Project Director will be announced for AEBL. Late 2007: Draft RFP. 2008: RFP and Site Selection. 2009/2010: CDR. 2011: Project Engineering and Design funding.

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Recommendations for the 2007 NSAC Long Range Plan

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.

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Argonne has chosen a path forward for an advanced exotic beam facility that

Complements the major investments in Europe and Japan in fast-beam fragmentation facilities by focusing on unique reaccelerated exotic beams. The facility will provide the full capabilities of stopped, reaccelerated and in-flight beams.

200 MeV/u superconducting linac driver will provide higher yields of all isotopes.

With reaccelerated beams based on gas-stopping and ISOL, vastly exceeds the capabilities of all reaccelerated beam facilities.

Provides the higher reaccelerated beam energies needed for some of the science (single-particle structure and pairing).

Can be built for about ½ the cost of RIA (~$550 M) by capitalizing on existing Argonne strengths and facilities.

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

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

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How do you make exotic beams?

• Fast Gas Catcher to combine advantages of fragmentation and stopped beams.

• Superconducting driver linac and post-accelerator for all ions from hydrogen to uranium.

• Acceleration of ions in multiple charge states to increase performance.

• Realizable designs for high power (>100 kW) targets.

• Efficient reacceleration of 1+ charge states.

Current Techniques A Better Way

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For reaccelerated and stopped beams this is a absolutely unique facility

Relative yields for a 200 MeV/u Advanced Exotic Beam Facility (AEBL) vs RIA and 50 kW ISOL-only facility

Better everywhere and the yellow regionsare uniquely available with AEBL

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Accelerator Physics – recent R&D results Continued major progress with superconducting niobium resonator development

– Design completed for new electropolishing system for ILC cavities (to be installed in the new ANL-FNAL surface processing facility at Argonne).

– Optimized EM designs of next-generation very low beta cavities with 1.5 & 3 times lower peak surface E- and B-fields, respectively, relative to Eacc.

– ANL-JLAB-LBNL collaboration verified very low microphonics of triple-spoke resonators in CW operation.

Continued development of parallel processing beam dynamics simulations: TRACK

– Improved algorithms for space charge – excellent scaling.

– Progress towards the “model-driven accelerator” concept. State of the art tools for advanced fragment separator design.

– Nuclear physics effects integrated into high-order optics optimization code. Thin-film liquid lithium charge stripping:

– High velocity ~10 micron thick film was demonstrated. Extended intensity range of the gas catcher technology (see next slide):

– New electrode geometry extended count rate capability to over 5 x 108/s with excellent efficiency.

Prototype CW RFQ for the AEBL driver was successfully tested to full power.

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On-going progress: Gas catcher technology and ATLAS upgrades Recent developments have extended the intensity range of the gas

catchers for AEBL and CARIBU:

Californium Rare Ion Breeder Upgrade allows us to produce new radioactive beams now and test significant technologies under production conditions. Operation begins in FY09.

Plan for Super-Caribu would increase CARIBU intensities by an order of magnitude and allow earlier start of construction of important elements of AEBL

•First tests at high intensity beamline in Sept and Oct 06 showed efficiencies near the AEBL goal obtained at up to 109

incoming particles per second

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AEBL2016

ReacceleratedRare Isotope

Beams

ISAC-II2009

How the suite of international facilities addresses the full program of rare isotope science

FAIR2013

RIKEN2007

Stored RareBeams

In-flight Rare Isotope Beams

StoppedRare Isotopes

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Alternatives

Many from outside Nuclear Physics speculate that a high power proton linac could be a substitute. – such a facility cannot do much of the physics (as stressed in RISAC

report).– directly competes with existing facilities such as ISAC and ISOLDE.

Such a facility at FNAL might be

well suited for beta beams for the

neutrino program. – Mats Lindross from CERN

visiting May 24.

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Bottom Line

A site decision is expected by one year from now.

Accelerator R&D funding continues.

We expect project funding to start in FY09 (CDR).

We want to find ways to make FNAL an integral part of project.

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CARIBU: Integrating Concepts & Gaining Experience for AEBL

Gas Catcher

High Resolution Isotope Separator

Charge Breeding in ECR Source

Post-acceleration of weakbeams

CARIBU Costs: $ 4.75 M CARIBU Completion: 2nd quarter FY09

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SuperCARIBU layout

SuperCARIBU is a significant upgrade of the capabilities of the ATLAS facility with CARIBU by:• Using low-Q acceleration and stripping to gain factors of 5 in efficiency,• Providing increased experimental space for stopped beam and astrophysics beam experiments,• Increasing the source fission rates, for example by using Cf-254 as the source material.