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Facility For Rare Isotope Beams. Bradley M. Sherrill FRIB Michigan State University. Facility for Rare Isotope Beams, FRIB Broad Overview. Driver linac capable of E/A 200 MeV for all ions, P beam 400 kW Experimental capabilities for reaccelerated, stopped and in-flight beams
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Facility For Rare Isotope Beams Bradley M. SherrillFRIBMichigan State University
Facility for Rare Isotope Beams, FRIB Broad Overview • Driver linac capable of E/A 200 MeV for all ions, Pbeam 400 kW • Experimental capabilities for reaccelerated, stopped and in-flight beams • Upgrade options (tunnel can house E/A = 400 MeVuranium driver linac, ISOL, multi-user capability …)
From Where We areto Baseline to Completed FRIB The preliminary choices will be reexamined with community input, more peer review and with DOE review and approval • Alternatives will be documented in a Conceptual Design Report (CDR) together with the preferred alternatives indicated. The CDR is subject to DOE approval.Important user input at the FRIB Equipment Workshop Feb 20-22 in East Lansing • Following Preliminary Engineering and Design, FRIB will have performance baseline (scope, cost, schedule) defined. This baseline is subject to DOE approval. • After detailed design, project starts construction (subject to DOE approval) • Pre-operations after construction leads to project completion (subject to DOE approval) CD-1 CD-2 Feb 2004 Q3 2010 Q3 2012 Q3 2013 > Sep 2017 CD-3 CD-4 CD4 Range 10/2017 to 2/2019
Alternatives Analysis: FRIB Folded layout Fragment Separators Experimental Areas ECR FRIB LINAC Switchyard/ Production Area Light Ion Injector (upgrade) Cryoplant
Science Drivers for FRIB Taken from the NRC Rare Isotope Science Assessment Committee (RISAC) Report, 2007 National Academies Press • Nuclear Structure • Explore the limits of existence and study new phenomena • Possibility of a broadly applicable model of nuclei • Probing neutron skins • 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* • Other Scientific Applications • Stockpile stewardship, materials, medical, reactors* * ISOL required for part or all of the program
Examples of Scientific Goals of FRIB that Drive Specifications • Produce and study nuclei along the drip lines at A≈100 • Produce and study nuclei in the r-process including at N=126 • Provide reaccelerated beams capabilities, e.g. 54Ca (astrophysics, fusion, transfer, COULEX, etc.) • Study benchmark nuclei, e.g. 60Ca • Superheavy element studies and fundamental symmetries experiments require that ISOL production by 600 MeV protons be an option
What New Nuclides Will FRIB Produce? After fragment separator • FRIB will produce more than 1000 new isotopes at useful rates • Many isotopes are produced in fragmentation and in-flight fission at greater than 1010/s • Special cases, e.g., 15O will have 2x1010/s • For reaccelerated beam rates we assume only 1% efficiency for the gas cell at greater than a few 108/s Reaccelerated Rates are available at http://groups.nscl.msu.edu/frib/rates/
Stopped beam area (operational in 2010/2011) ReA3 – Funded by MSU (operational in 2011 for rare isotope beams) ReA12 - in FRIB project (2015) Stopped and Reaccelerated Beams Notional layout and equipment shown
Theory Road Map: Nuclear Structure and Reactions • Theory Road Map – comprehensive description of the atomic nucleus • Ab initio models – study of neutron-rich, light nuclei helps determine the force to use in models • Configuration-interaction theory; study of shell and effective interactions • The universal energy density functional (DFT) – determine parameters • The role of the continuum and reactions and decays of nuclei • IMPORTANT: Understand and select sensitive measurements Energy density functional Configuration interaction Ab initio Continuum
Known half-life N=126 NSCL reach RISACKey Nuclei First experiments (70) Yb (69) Tm (68) Er Future Reach (67) Ho (66) Dy Reach of FRIB for r-process Studies • βdecay properties • masses (Trap + TOF) • (d,p) to constrain (n,γ) • fission barriers, yields 82 FRIB reachfor (d,p) 126 50 Current reach 82 28 FRIB reach forhalf-lives 50 H. Schatz
Reach of FRIB for Novae and X-ray Burst Reaction Rate Studies rp-process 10>10 109-10 108-9 107-8 direct (p,g) 106-7 direct (p,a) or (a,p)transfer key reaction rates can beindirectly measuredincluding 72Kr waiting point 105-6 (p,p), some transfer 104-5 102-4 most reaction rates up to ~Sr can bedirectly measured All reaction rates up to ~Ti can be directly measured H. Schatz 15O projected intensity of available at >1010/s level
Tests of Nature’s Fundamental Symmetries • Angular correlations in β-decay and search for scalar currents • Mass scale for new particle comparable with LHC • 6He and 18Ne at near 1012/s • Electric Dipole Moments • 225Ac, 223Rn, 225Ra, 229Pa (30,000 more sensitive than 199Hg) • Parity Non-Conservation in atoms • weak charge in the nucleus (francium isotopes; 109/s) • Unitarity of CKM matrix • Vud by super allowed Fermi decay • Probe the validity of nuclear corrections G. Savard e γ 212Fr Z
Rare Isotopes For Society Isotope harvesting is in the FRIB scope • Isotopes for medical research • Examples: 47Sc, 62Zn, 64Cu, 67Cu, 68Ge, 149Tb, 153Gd, 168Ho, 177Lu, 188Re, 211At, 212Bi, 213Bi, 223Ra (DOE Isotope Workshop) • -emitters 149Tb, 211At: potential treatment of metastatic cancer • Reaction rates important for stockpile stewardship – non-classified research • Determination of extremely high neutron fluxes by activation analysis • Rare isotope samples for (n,g), (n,n’), (n,2n), (n,f) e.g. 88,89Zr • Same technique important for astrophysics • More difficult cases studied via surrogate reactions (d,p), (3He,axn) … • Tracers for Geology, Condensed Matter (8Li), material studies, …
ISOL Background: Expert Panel Recommendations • NSAC RIB Task Force 2007 (Symon’s committee) – “First, in contrast to the gas stopper, we view the ISOL target as a part of the experimental equipment rather than a necessary core capability of the accelerator. Provision should be made to accommodate such a target, but the decision to construct it should be based on the existence of a strong collaboration and an approved experimental program.” • 2007 NSAC LRP - “physicists have begun planning a next-generation Facility for Rare Isotope Beams (FRIB), which will deliver the highest intensity beams of rare isotopes available anywhere. But FRIB will not be available for a decade. So in the meantime, physicists hope to continue developing a comprehensive picture of atomic nuclei by strengthening operations and carrying out modest upgrades at the National User Facilities (at ANL’s ATLAS, ORNL’s HRIBF, and MSU’s NSCL)” • OECD 2008 Working Group on Nuclear Physics Report - “The future nuclear physics facilities such as the multi-megawatt ISOL systems and electron-ion collider would also require a global R&D effort.”
ISOL at FRIB • Community Input in support of ISOL at FRIB • Consensus statement from the ANL FRIB Workshop, May 2009 “We support including space to implement an ISOL option.” • Strong support and scientific case presented at the Workshop on Rare Atom Physics in Ann Arbor, MI June 2009 • Collaboration meeting held in Aug 2009 at MSU • It seems clear ISOL is important for the future of rare isotope science and FRIB • User interest • At least two of the RISAC science drivers (heavy elements and EDM searches) most likely require ISOL • Infrastructure to implement ISOL is included in FRIB • Implementation of ISOL at FRIB may cost tens of M$ ( detailed cost estimates are underway but not complete) • For early and effective implementation of ISOL at FRIB it is necessary and important to continue ISOL programs in the U.S.
Summary • FRIB will allow production of a wide range of isotopes • Extend our searches for the limits to nuclear stability • Answer key questions on the nature of the universe (chemical history, mechanisms of stellar explosions) • Significant opportunities for the tests of fundamental symmetries • Potential for important societal applications • ISOL will likely be an important production mechanism for FRIB and the infrastructure to make easy implementation is included in the base facility • Continued ISOL programs and developments are important; ORNL/HRIBF is the U.S. center for those activities