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FRIB Physics Program

FRIB Physics Program. Brad Sherrill Facility for Rare Isotope Beams 26 June 2013. Outline. Development of a comprehensive model of atomic nuclei – H ow do we understand the structure and stability of atomic nuclei?

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FRIB Physics Program

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  1. FRIB Physics Program Brad Sherrill Facility for Rare Isotope Beams 26 June 2013

  2. Outline • Development of a comprehensive model of atomic nuclei – How do we understand the structure and stability of atomic nuclei? • Understanding the origin of elements and modeling of extreme astrophysics environments • Use of atomic nuclei to test fundamental symmetries (e.g. in a search for CP violation) • Applied isotope science – new applications of isotopes RHIC Users Meeting June 2013

  3. One of the Challenges – How many elements? Claims for up to Z=118, but much beyond requires theory – application of Density Functional Theory - P. Pyykkö: Phys. Chem. Chem. Phys. 13, 161-168 (2011) “Half of chemistry is undiscovered.” - Another view – above Z=122 all chemistry is the same due to relativistic effects - For stability of Z>120 see also Jachimowicz, Kowal, Skalski, PRC 83 (2011) RHIC Users Meeting June 2013

  4. One of the Challenges – Origin Elemental Abundances in our Solar System • Stars are mostly made of hydrogen and helium, but each has a fairly unique pattern of other elements • The abundance of elements tell us about the history of events prior to the formation of our sun • The plot at the right shows the composition in the visible surface layer of the Sun (photosphere) • How were these elements created prior to the formation of the Sun? Asplund, M., Grevesse, N., Sauval, A.J., Scott, P.: Annu. Rev. Astron. Astrophys. 47, 481 (2009) RHIC Users Meeting June 2013

  5. Challenge: Nuclei from NN Interactions • How do we model atomic nuclei? QCD, but we need approximations • Modern approaches to NN potentials include • QCD Inspired EFT - Epelbaum, Machleidt, … • String Theory Inspired – Hashimoto … • Lattice QCD – Detmold, Aoki … Theory “Data” N. Ishii, S. Aoki, T. Hatsuda, Phys. Rev. Lett. 99, 022001 (2007) RHIC Users Meeting June 2013

  6. Goal: Comprehensive Understanding of Nuclei • Two-nucleon, three-nucleon, etc. interactions are a foundation. What if they are imbedded in a nucleus? • Are protons and neutrons in medium modified from their free structure? Maybe: EMC Effect and recent results from JLAB indicate yes • What affect does nucleon structure have on nuclear structure? • What other effects are present but unrecognized? 12C Nucleus RHIC Users Meeting June 2013

  7. The Road Map: A Comprehensive Model of Atomic Nuclei Rare isotopes play a key role at each step. Step 1: Start from NN forces (ab initio theory) and study of light rare isotopes to determine the interactions of nucleons in nuclei and connect these to QCD by comparison to lattice calculations of NN, NNN forces, and couplings in EFT Step 2: For mid-mass nuclei use configuration interaction models. The degrees of freedom and interactions must be determined from rare isotopes Step 3: Use density functional theory, DFT, to connect to heavy nuclei. Rare isotopes help determine the form and parameters of the DFT. RHIC Users Meeting June 2013

  8. Theory Road Map: Comprehensive Model of Nuclear Structure and Reactions • Pictoral version of the Theory Road Map – Goal is a “standard model” for understanding nuclei • Colors indicate the yields from FRIB. Access to a wide range and nuclei along the drip lines is critical Energy density functional Configuration interaction Ab initio Continuum Relationship to QCD (LQCD) RHIC Users Meeting June 2013

  9. Comparison of Calculated and Measured Binding Energies with NN models NN potential NN + NNN potential Greens Function Monte Carlo techniques allow up to mass number 12 to be calculated Blue 2-body forces V18 S. Pieper B.Wiringa, et al. RHIC Users Meeting June 2013

  10. New information from exotic isotopes S. Pieper B.Wiringa, et al. NN + improved NNN potential Properties of exotic isotopes are essential in determining NN and NNN potentials • Neutron rich nuclei were key in determining the isospin dependence of 3-body forces and the development of IL-2R from UIX • New data on exotic nuclei continues to lead to refinements in the interactions RHIC Users Meeting June 2013

  11. Current status of the GFMC calculations Carlson, Pieper, Wiringa, et al. RHIC Users Meeting June 2013

  12. Application of GFMC technique to reactions of nuclei important to BB Nucleosynthesis • Resonance states in 5He (n+4He) K. Nollett, et al, PRL 2007; motivated by BBN modeling RHIC Users Meeting June 2013

  13. Importance of 3N forces Gandolfiet al., PRC85, 032801 (2012) Nazarewiczet al. Big Bang Nucleosynthesis: Calculate all key reactions Neutron star masses Half-life of 14C (Maris, Navratilet al. PRL), structure of calcium isotopes (Wienholtzet al. Nature), etc. RHIC Users Meeting June 2013

  14. Construct NN Potentials: EFT based on QCD Symmetries – “Chiral” Cut-off parameter Λ ≅ 500MeV Contact interactions have constants that are fit to experiment Picture from E. Epelbaum Effective Field Theory, EFT, based on QCD Symmetries (Weinberg,Epelbaum ,Furnstahl, Machleidt, van Kolck, Navrátil,… ) Use the features of the pion in constructing an effective theory RHIC Users Meeting June 2013

  15. Standard Shell Model • Mayer and Jensen Nobel prize in 1963 “"for their discoveries concerning nuclear shell structure" Magic Numbers N l2potential Spin-Orbit picture NielsWalet RHIC Users Meeting June 2013

  16. Stability of Magic Nuclei Harder to excite RHIC Users Meeting June 2013

  17. Stability of Magic Nuclei 20 protons Harder to excite 16 protons 14 protons RHIC Users Meeting June 2013

  18. Surprise: Changing Magic Numbers Harder to excite Reason: A tensor force that depends on angular momentum and isospin (Otsuka et al.) RHIC Users Meeting June 2013

  19. Step 3: Density Functional Theory • Widely used in Chemistry– based on Hohenberg-Kohn (Phy Rev 136) • Relies on the variation concept where observables are treated as variational parameters, e.g. local density ρ(r) and its derivative • We don’t know the correct form for nuclei. Example: Skyrme functional • Use rare isotopes to test functional forms, determine parameters, provide insight for improvements N. Schunck, Exotic Beam Summer School 2012 RHIC Users Meeting June 2013

  20. Prediction of the limits of the nuclear landscape J. Erler et al., Nature 486, 509 (2012) 265 stable isotopes, 3100 observed, more like 2000 “known”, 6900(600) possible RHIC Users Meeting June 2013

  21. Weakly bound isotopes have unique features “Normal” “Halo” Tanihata PRL1985 “Skin” Tanihata PLB1992 80Ni 11Li 220Rn New Science: Pairing in low-density material, new tests of nuclear models, open quantum system, interaction with continuum states - Efimov States - Reactions see e.g. H.-W. Hammer and L. Platter, Ann. Rev. Nucl. Part. Sci. 60, 207 (2010) RHIC Users Meeting June 2013

  22. Weakly Bound Nuclei are Open Quantum Systems Dobaczewski et al., Prog. Part. Nucl. Phys. 59, 432 (2007) W Nazarewicz RHIC Users Meeting June 2013

  23. The Origin of the Elements • One of 11 Science Questions for the 21stcentury • How were the elements from iron to uranium made? • Where and how does the r-process occur? RHIC Users Meeting June 2013

  24. New data on elemental abundances: Surveys and Large Aperture Telescopes Hubble Space SUBARU The measurement of elemental abundances is at the forefront of astronomy using large telescopes Large mirrors enable high resolution spectroscopic studies in a short time (Subaru, Hubble, LBT, Keck, …) Surveys provide large data sets (SDSS-III, RAVE, LAMOST, SkyMapper, LSST…) Future missions: JWST - “is specifically designed for discovering and understanding the formation of the first stars and galaxies, measuring the geometry of the Universe and the distribution of dark matter, investigating the evolution of galaxies and the production of elements by stars, and the process of star and planet formation.” RHIC Users Meeting June 2013

  25. Simulation of Solar System Abundances Timmes, Woosley, WeaverAstro. Journal 1995 • Parameters: • Supernovae type Ia and II • Number (77 supernovae with Ms 11-40 Msun) • Progenitor mass distributions • Age of the galaxy • … • Results: • SN rate1/3 comes from type Ia • They reproduce measured 7Li abundance metalicityvs. time etc. Success ! ? Note above A=72 we can’t model RHIC Users Meeting June 2013

  26. Neutron-capture process leading to elements heavier than iron Reaction path fission β- (γ ,n) AZ … (n,γ) (n,γ) • E. M. Burbidge, G. R. Burbidge, W. A. Fowler, and F. Hoyle. (1957). "Synthesis of the Elements in Stars". Rev Mod Phy 29: 547, must be an r-process (10% of gold from s-process) • Rapid neutron capture process, r-process • Fast, few second duration • Neutron density of 1020-28 n/cm3 • Runs out to where (n,γ) and (γ,n) are similar in rate • Adds 30-40 neutrons • Site unknown RHIC Users Meeting June 2013

  27. Advances in Theoretical Astrophysics • We now have several robust, self-consistent r-process models; to test them against observations, we need nuclear data Neutrino Driven Wind Hoffman et al. 2008 Hoffman et al. 2008 10 Winteler et al. 2012 1 100 80 60 40 Mass number NeutronStar Mergers Korobkin et al. 2012 MHD Supernova Jets abundance Mass number RHIC Users Meeting June 2013

  28. Uncertainty between models and nuclear properties Astrophysics Nuclear physics 101 Hot bubble ETFSI-Q masses Classical model ETFSI-1 masses 100 Same nuclear physics Same (classical) r-process model 10-1 Abundance 10-2 10-3 Freiburghaus et al. 1999 10-4 Mass number Mass number H. Schatz RHIC Users Meeting June 2013

  29. New Facilities will Enable the Needed Breakthrough in Nuclear Physics Different key-regions probe different model aspects when compared to observations N=126 N=82 Critical region probes:Main r-process parametersProduction of actinides Critical region: Disentangler-processes Critical region probes:r-process freezeout behavior(Mumpower et al. 2012) Critical region probes:Main r-process parameters H Schatz Critical region probes:Neutrino fluence RHIC Users Meeting June 2013

  30. FRIB reachfor T1/2, masses,and β-delayed neutron emission(Overlap with applications!) New Facilities will Enable the Needed Breakthrough in Nuclear Physics Different key-regions probe different model aspects when compared to observations N=126 N=82 Critical region probes:Main r-process parametersProduction of actinides Critical region: Disentangler-processes Critical region probes:r-process freezeout behavior(Mumpower et al. 2012) Critical region probes:Main r-process parameters H Schatz Critical region probes:Neutrino fluence RHIC Users Meeting June 2013

  31. Stellar Hydrogen Explosions:Common (100/day) and Not Understood www4.nau.edu • Open questions • Neutron star size • Short burst intervals • Multiple peaked bursts • Nature of superbursts • Ejected mass (Nucleosynthesis) • Observable gamma emitters • Why such a variety • Path to Iasupernovae RHIC Users Meeting June 2013

  32. Making Sense of X-ray BurstObservations • Need nuclear data on rare isotopes to create reliable model templates to analyze observations Amthor, Cyburt et al. 2012 Galloway et al. GS 1826-24 Burst profiles depend on nuclear rates • With accurate model templates • Absolute peak flux, distance • H/He composition • Redshift + color correction(distance and anisotropy independent) neutron star size Redshiftvariation ~5000 widely varying bursts Zamfir et al. 2012 RHIC Users Meeting June 2013

  33. FRIB Reach for Novae and X-ray burst reaction rate studies rp-process 10>10 109-10 108-9 key reaction rates can be indirectly measured including 72Kr waiting point 107-8 direct (p,g) 106-7 direct (p,a) or (a,p)transfer 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 RHIC Users Meeting June 2013

  34. Cackett et al. 2006 (Chandra, XMM-Newton) Rare Isotope Crusts of Accreting Neutron Stars KS 1731-260(Chandra) • Nuclear reactions in the crust set thermal properties (e.g. cooling) • Can be directly observed in transients • Directly affects superburst ignition Understanding of crust reactions offers possibility to constrain neutron star properties (core composition, neutrino emission…) H. Schatz RHIC Users Meeting June 2013

  35. Where do Neutrons Drip? Known mass FRIB reach:dripline up to A~100 + mass measurements + EC rates via charge exchange Driplineknown K.-Y. Lau, M. Beard, P. Shternin, et al., to be published RHIC Users Meeting June 2013

  36. Are the fundamental interactions that are basic to the structure of matter fully understood? Adopted from Savard et al. • Angular correlations in β-decay and search for scalar currents • Mass scale for new particle comparable with LHC • 6He and 18Ne at 1012/s • Electric Dipole Moments • 225Ra, 223Rn, 229Pa (10,000x more sensitive than 199Hg; 229Pa > 1010/s) • Anapole moment in Fr atoms • Understanding of weak interactions in nuclei (francium isotopes; 1010/s) • Unitarity of CKM matrix • Vud by super allowed Fermi decay • Probe the validity of nuclear corrections e γ 212Fr Z RHIC Users Meeting June 2013

  37. Rare Isotopes For Society • FRIB offers fast development of 1000s of isotopes (via harvesting) • 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 • Cancer therapy of hypoxic tumors based on 67Cu treatment/64Cu dosimetery • Reaction rates important for stockpile stewardship and nuclear forensics • 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 • More difficult cases studied via surrogate reactions (d,p), (3He,axn) … • We can produce quantities of separated fission products for tests of detection techniques • Tracers for Marine Studies (32Si), Condensed Matter (8Li), industrial tracers (7Be, 210Pb, 137Cs, etc.), … • Data for advance reactor design and destruction of nuclear waste RHIC Users Meeting June 2013

  38. Summary • We are entering a new era in nuclei physics when we can produce and study key rare isotopes: • Development of a standard model for nuclei • What are the heaviest elements possible? • What is the origin of the nuclear force in QCD and EW • In 15 years we might know the answer • Foundation for astrophysical modeling • With new rare isotopes we will be able to better model stellar processes • We will have the ability to understand the history of a star (or meteorite) • Modeling of neutron stars, novae, supernovae will be on a more solid footing • Search for symmetry violations, e.g. atomic EDMs • enhanced sensitivity from FRIB will allow most of the interesting EDM scales to be covered RHIC Users Meeting June 2013

  39. Major US Project – Facility for Rare Isotope Beams, FRIB • Funded by DOE Office of Science – 2020 completion • Key Feature is 400kW beam power (5 x1013 238U/s) • Separation of isotopes in-flight • Fast development time for any isotope • Suited for all elements and short half-lives RHIC Users Meeting June 2013

  40. New Insight from Mass Model Comparison to Data • HFB-14: Hartree-Fock-Bogoliubov w/delta pairing force • S. Goriely, M. Samyn, J.M. Pearson, Phys. Rev. C75 (2007) 064312 • MEHFB14 – MEAME2003 • ME = (Actual mass – A u) x 931.5 MeV/u • u = atomic mass unit (931.5 MeV) J. Duflo, A.P. Zuker, Phys. Rev. C52 (1995) R23 Shell Model Based MEDZ – MEAME2003 Less bound than data More bound than data www.nuclearmasses.org RHIC Users Meeting June 2013

  41. “Ab Initio” start with NN forces N. Ishii, S. Aoki, and T. Hatsuda, Phys. Rev. Lett. 99, 022001 (2007) • Approach: Construct NN potentials based on neutron and proton scattering data and properties of light nuclei (Bonn, Reid, Illinois AV18, Nijmegen, etc.) • More recent approach is to construct the potentials some more fundamental theory • QCD Inspired EFT • String Theory Inspired – Hashimoto et al • Lattice QCD RHIC Users Meeting June 2013

  42. Configuration Interaction Models • The interaction of nuclei create a “mean field”. We think of nucleon moving in this potential. • Shell Model is the most common in nuclear science • Solve the equation HΨ=EΨ • Introduce a basis (usually harmonic oscillator) and solve the matrix equation • Can assume inert closed cores for certain nuclei (e.g. N=Z=20) • No core shell model does not make this assumption • All shell models use effective operators (interactions depend on model space 12C RHIC Users Meeting June 2013

  43. “No Core” Shell Model • Use ab initio interactions derived by some means like EFT or fits to NN scattering in a shell model • Diagonalize in a large basis of many-body states From A. Poves, International School on Exotic Beams, Santiago de Compostela, September 4-11 2010 (see also J Vary, etc.) RHIC Users Meeting June 2013

  44. Known mass Electron capture rates Mass measurements Drip line established Haensel & ZdunikAstroJourn1990, 2003, 2008 Gupta et al.AstroJourn 2006 FRIB Reach For Crust Processes • Interesting set of reactions leading to proton-rich material converted to neutron-rich material H. Schatz RHIC Users Meeting June 2013

  45. There are a number of nucleosynthesis processes that must be modeled fission Sample reaction paths (α,γ) (p,γ) β- (α,p) AZ (n,2n) (n,γ) β+ , (n,p) (γ,p) Black - FRIB critical for modeling Big Bang Nucleosynthesis pp-chain CNO cycle triple alpha Helium, C, O, Ne, Si burning s-process r-process rp-process νp – process p – process α - process fission recycling Cosmic ray spallation pyconuclear fusion RHIC Users Meeting June 2013

  46. How many isotopes might exist? • Estimated Possible: Erler, Birge, Kortelainen, Nazarewicz, Olsen, Stoitsov, Nature 486, 509–512 (28 June 2012) , based on a study of EDF models • “Known” defined as isotopes with at least one excited state known (1900 isotopes from NNDC database) • Represents what is possible now RHIC Users Meeting June 2013

  47. The Number of Isotopes Available for Study at FRIB (next generation facilities) • Estimated Possible: Erler, Birge, Kortelainen, Nazarewicz, Olsen, Stoitsov, Nature 486, 509–512 (28 June 2012) , based on a study of EDF models • “Known” defined as isotopes with at least one excited state known (1900 isotopes from NNDC database) • For Z<90 FRIB is predicted to make > 80% of all possible isotopes RHIC Users Meeting June 2013

  48. A Vision RHIC Users Meeting June 2013

  49. Unusual Isotopes to Test Fundamental Symmetries – Electric Dipole Moment Search • A Electric Dipole Moment, EDM, • Violates CP symmetry • Large value would be evidence for physics beyond the standard model • Possible explanation for matter dominance over antimatter Wolfgang Korsch RHIC Users Meeting June 2013

  50. EDM Searches in Three Sectors • Best current limit in nuclei is from WC Griffiths et al. PRL 102, 101601 (2009) d (e-cm) < 3.1 x10-29 • Rare isotopes offer the chance for enhanced sensitivity • Current efforts: • 223Rn TRIUMF: E929 Spokespersons T. Chupp (Univ of Michigan), C. Svensson (Guelph) • 225Ra Argonne National Laboratory: Z-T Lu • 225Ra at TRIμP at KVI Quark EDM Nucleons (n, p) Physics beyond the Standard Model: SUSY, etc. Quark Chromo-EDM Nuclei (Hg, Ra, Rn) Electron in paramagnetic molecules (YbF, ThO) Electron EDM Z-T Liu, Univ. of Chicago RHIC Users Meeting June 2013

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