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Science of rare isotopes: connecting nuclei with the universe

Science of rare isotopes: connecting nuclei with the universe Rutgers University Colloquium, November 5, 2008. Two take-away messages: Nuclear scientists, experimentalists and theorists, are getting better and better at controlling short-lived nuclei, in particular those which are useful

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Science of rare isotopes: connecting nuclei with the universe

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  1. Science of rare isotopes: connecting nuclei with the universe Rutgers University Colloquium, November 5, 2008 • Two take-away messages: • Nuclear scientists, experimentalists and theorists, are getting better and better at controlling short-lived nuclei, in particular those which are useful • Rare isotopes are the key to answering questions in many areas of science • Introduction • Territory • Science • Connections and Relevance • Perspectives

  2. Prelude

  3. Munster 1544 Jaillot 1694 Lotter 1760

  4. reduction complexity The Quantum Ladder Galaxy clusters Galaxies Stars Planets macroscopic Living Organisms, Man-made Structures Cells, Crystals, Materials Molecules Atoms Nuclei Elementary Particles (baryons, mesons) Quarks and Leptons subatomic Super- strings ? ???

  5. Nuclear Structure

  6. Introduction

  7. Some nuclei are more important than others - + - + - + tests of fundamental laws of nature nuclear structure + - + - 45Fe 149Tb astrophysics applications 18F,22Na 225Ra Over the last decade, tremendous progress has been made in techniques to produce designer nuclei, rare atomic nuclei with characteristics adjusted to specific research needs

  8. How do protons and neutrons make stable nuclei and rare isotopes? What is the origin of simple patterns in complex nuclei? What is the equation of state of matter made of nucleons? What are the heaviest nuclei that can exist? When and how did the elements from iron to uranium originate? How do stars explode? What is the nature of neutron star matter? How can our knowledge of nuclei and our ability to produce them benefit the humankind? Life Sciences, Material Sciences, Nuclear Energy, Security Questions that Drive the Field Physics of nuclei Nuclear astrophysics Applications of nuclei

  9. Designer Nuclei in Nuclear Landscape superheavy nuclei 62Ga 78Ni 208Pb 132Sn 45Fe 11Li 42Si 283112 45Fe 101Sn 149Tb 42Al 43Al 40Mg 99Sn 100Sn Novel decay modes 180Hg 95Cd 96Cd 82 126 Extending the limits 82 1228 28 20 50 8 28 Probing existence/changes of the shell structure far from stability 2 20 8 2

  10. Magicity is a fragile concept Near the drip lines nuclear structure may be dramatically different.

  11. Structure of rare isotopes Old paradigms revisited. Crucial input for theory No shell closure for N=8,20,28 for drip-line nuclei new shells at 14,16,32…

  12. Neutron skins neutrons 0.12 0.08 0.04 0.00 0.12 0.08 0.04 0.00 100Sn Sn isotopes protons 7 N/Z=1 density (nucleons/fm3) neutrons radius (fm) 100Zn protons 6 The only laboratory access to matter made essentially of pure neutrons N/Z=2.33 60 80 100 120 0 2 4 6 8 r (fm) neutron number

  13. Neutron-rich matter and neutron skins Pygmy dipole Furnstahl 2002 skin 208Pb pressure Bulk neutron matter equation of state Constraints on the mass-vs-radius relationship of neutron stars Giant dipole E1 strength GSI 2005

  14. The Limit of Mass and Charge: superheavies Chemistry Holy grail… Nature 447, 72 (2007) GSI: confirmation Beams of neutron-rich rare isotopes are crucial in this quest Current Affairs… 118 116 115 114 RIKEN 113 Dubna LLNL GSI

  15. X-ray burst 4U1728-34 331 Frequency (Hz) 330 329 328 327 10 15 20 Time (s) How does the physics of nuclei impact the physical universe? • What is the origin of elements heavier than iron? • How do stars burn and explode? • What is the nucleonic structure of neutron stars? p process s-process r process rp process Nova Neutron star Crust processes T Pyxidis stellar burning protons neutrons

  16. Rare isotope measurements for novae Hernanz et al, 2003 ESA INTEGRAL Satellite searching for novae signatures O Ne Mg Nova Nova QUVul, HST 26gAl(p,)27Si TRIUMF (2006) 17F(p,)18Ne 18Ne capture reaction 21Na(p,)22Mg TRIUMF (2004) 17F energy loss scattered 17O scattered on resonance (600 keV) HRIBF (2008) total energy Example of synergy between nuclear science and astronomy predicted -ray flux from decaying radionuclides 18F, 22Na... synthesized in explosion Synthesis of e.g. 18F, 22Na, (26Al) very important for characteristic g-ray emission from nova

  17. r (apid neutron capture) process Supernova r-process (,n) campaign: towards 110Zr (NSCL) r-process (d,p) campaign: around 132Sn (HRIBF) 107Zr: halflife 130,132Sn(d,p)131,133Sn 133Sn masses, decays, level structure, and reactions are all important for calculating r-process reaction flow The origin of about half of elements heavier than iron Goes through neutron-rich rare isotopes http://www.jinaweb.org/html/gallery3.html

  18. - + - + - + + - + - 225Ra Testing the fundamental symmetries of nature Experiments addressing questions o the fundamental symmetries of nature can take advantage of certain exotic isotopes because aspects of their structure greatly magnify the size of the symmetry-breaking processes being probed EDM searches in

  19. 2008 Nobel Prize in Physics

  20. Superallowed Fermi 0+ 0+-decay studies (testing the unitarity of the Cabibbo-Kobayashi-Maskawa matrix) 62Ga@ TRIUMF (2006-2008) T1/2=116.100(22)ms, BR=99.858(8)% Jyväskylä (2008) BR=99.893(24) 34Ar, 34Cl@TAMU (2006) T1/2=843.8(4) ms,1.5268(5)s 38mK@TRIUMF (2008) BR=99.967(4)% with new symmetry-breaking corrections: with new symmetry-breaking corrections: 46V@ ANL (2005) Q=7052.90(40) keV 46V@ Jyväskylä (2006) Q=7052.72(31) keV Munich tandem (2008) Q=7052.10(31) keV 50Mn,54Co@Jyväskylä (2007) Q=7634.48(7), 8244.54(10) keV 26mAl,42Sc@Jyväskylä (2006) Q=4232.83(13),6426.13(21) keV 26mAl @ISOLDE (2008) Q Half-life Q-value 0.9996(7) Branching Ratio • more cases measured… stay tuned… • Advances in isospin mixing calculations 38mK

  21. Nuclear Structure Theory Progress Report

  22. Links to CMP/AMO science!!! number of nuclei < number of processors!

  23. Coupled Cluster Theory Size Extensive! converged CCSD results for medium-mass nuclei with N3LO Medium-mass nuclei from chiral nucleon-nucleon interactions G. Hagen, T. Papenbrock, D.J. Dean and M. Hjorth-Jensen, Phys. Rev. Lett. 101, 092502 (2008)

  24. Mean-Field Theory ⇒ Density Functional Theory • Nuclear DFT • two fermi liquids • self-bound • superfluid • mean-field ⇒ one-body densities • zero-range ⇒ local densities • finite-range ⇒ gradient terms • particle-hole and pairing channels • Has been extremely successful. A broken-symmetry generalized product state does surprisingly good job for nuclei.

  25. Computational Strategy

  26. Strategy… From Ian Thompson

  27. (n+AXi) at energy Eprojectile Computational Workflow Eprojectile (UNEDF work) Target A = (N,Z) Ground state Excited states Continuum states TransitionDensities(r) Structure ModelMethods: HF, DFT, RPA, CI, CC, … Transitions Code UNEDF: VNN, VNNN…  Folding Code Veff for scattering Transition Potentials V(r) (Later: density-dependent & non-local) (other work) Deliverables Inelastic production Compound production Coupled ChannelsCode: FRESCO Partial Fusion Theory Hauser-Feshbach decay chains Residues (N’,Z’) Delayed emissions Compound emission Elastic S-matrix elements Voptical Preequilibrium emission Prompt particle emissions Fit Optical Potential Code: IMAGO Global optical potentials KEY: Code Modules UNEDF Ab-initio Input User Inputs/Outputs Exchanged Data Future research UNEDFReaction work

  28. Universal Nuclear Energy Density Functional http://unedf.org/ • Funded (on a competitive basis) by • Office of Science • ASCR • NNSA • 15 institutions • ~50 researchers • physics • computer science • applied mathematics • foreign collaborators • FIDIPRO • Warsaw • France/Belgium • Japan • 5 years …unprecedented theoretical effort ! [See http://www.scidacreview.org/0704/html/unedf.html by Bertsch, Dean, and Nazarewicz]

  29. Example: Large Scale Mass Table Calculations Science scales with processors M. Stoitsov HFB+LN mass table, all nuclei • 9,210 nuclei • 599,265 configurations • Using 3,000 processors - about 25 CPU hours Jaguar Cray XT4 at ORNL see MassExplorer.org

  30. Multimodal fission in nuclear DFT • Staszczak, A.Baran, • J. Dobaczewski, W.N.

  31. Connections and Relevance

  32. Connections to quantum many-body systems Complex Systems • Understanding the transition from microscopic to mesoscopic to macroscopic • Symmetry breaking and emergent phenomena • Pairing in finite systems • Quantum chaos • Open quantum systems • Dynamical symmetries and collective dynamics • Dilute fermion matter: • strongly correlated • very large scattering length (unitary limit) • Low-density neutron matter • Cold fermions in traps

  33. Societal Benefits

  34. Applications of Rare Isotopes How can our knowledge of nuclei and our ability to produce them benefit the humankind? • Stockpile stewardship and inertial fusion • Modeling the diverse reaction pathways driven by both neutrons and charged particles spanning an energy spectrum from about 0.1 to 16 MeV (analogous to the r-process) • Materials science • Rare-isotopes have broad applications in condensed matter and materials science as low density, very high signal to noise in situ detectors of local atomic environments. -NMR is an excellent example • Energy, transmutation of waste… • Can we use fast neutron reactors and accelerators for the mitigation of long-lived radioactive waste? • Can we design an economically competitive, energy efficient, reduced-waste nuclear reactor? • Medical and biological research • Applications of radionuclides (see below)

  35. What are the next medically viable radioisotopes required for enhanced and targeted treatment and functional diagnosis? Example: Targeted Alpha Therapy in vivo The radionuclide 149Tb decays to alpha particles 17 percent of the time and has a half-life of 4.1 hours, which is conveniently longer than some other alpha-emitting radionuclides. Lower energy alpha particles, such as in 149Tb decays, have been shown to be very efficient in killing cells, and their short range means that minimal damage is caused in the neighborhood of the target cells. -knife! First in vivo experiment to demonstrate the efficiency of alpha targeted therapy using 149Tb produced at ISOLDE, CERN G.-J. Beyer et al.Eur. J. Nucl. Med. and Molecular Imaging 33, 547 (2004)

  36. Survival of mice… 100 149 5 MBq Tb, 5 µg MoAb 90 80 70 no MoAb 60 300 µg MoAb, cold % of survived mice 50 40 5 µg MoAb, cold 30 20 10 0 0 20 40 60 80 100 120 Survival time, days 5*106 Monoclonal Antibody 2 days later the mice have been devided into 4 groups:

  37. Perspectives

  38. Experiment TRIUMF GSI NSCL GANIL ISOLDE RIKEN HRIBF FRIB Future major facilities Existing major dedicated facilities Radioactive Ion Beam Facilities Worldwide

  39. Connections to computational science 1Teraflop=1012 flops 1peta=1015 flops (next 2-3 years) 1exa=1018 flops (next 10 years) CRAY XT4 (Jaguar) No. 5, 260 TFlops CRAY XT5 (Jaguar, Kraken) petaflop machines Kraken

  40. 2007 NSAC Long Range Plan The Frontiers of Nuclear Science National Academy 2007 RISAC Report BPA RareIsotopeScience Assessment Committee “Nuclear science is entering a new era of discovery in understanding how nature works at the most basic level and in applying that knowledge in useful ways” • Exciting opportunities in: • Nuclear Structure • Nuclear Astrophysics • Tests of fundamental symmetries with rare-isotopes • Scientific Applications

  41. Outlook The study of rare isotopes makes the connection between the fundamental building block of matter, complex systems, and the cosmos • Exciting and transformational science; old paradigms revisited • Interdisciplinary science • Science relevant to society Over the last decade, tremendous progress has been made in techniques to produce designer nuclei, rare atomic nuclei with characteristics adjusted to specific research needs. Guided by unique data on short-lived nuclei, we are embarking on a comprehensive study of all nuclei based on the most accurate knowledge of nuclear interactions, the most reliable theoretical approaches, and the massive use of the computer power available at this moment in time. Many problems remain but the prospects are excellent. Thank You

  42. Backup

  43. 1, 2, 3, 4, 208, ∞

  44. NN and NNN interactions Effective-field theory (χPT) potentials Vlow-k unifies NN interactions at low energy Bogner, Kuo, Schwenk, Phys. Rep. 386, 1 (2003) • Quality two- and three-nucleon interactions exist • Not uniquely defined (local, nonlocal) • Soft and hard-core N3LO: Entem et al., PRC68, 041001 (2003) Epelbaum, Meissner, et al.

  45. Short-range correlations: a red herring

  46. Hagen et al, ORNL/UTK Ab initio: Reactions Nollett et al, ANL Coupled Clusters CC GFMC Quaglioni & Navratil, LLNL 2008 No Core Shell Model +Resonating Group Method 11Be: arXiv:0804.1560

  47. How many parameters are really needed? Spectroscopic (s.p.e.) Global (masses) Bertsch, Sabbey, and Uusnakki Phys. Rev. C71, 054311 (2005) Kortelainen, Dobaczewski, Mizuyama, Toivanen, arXiv:0803.2291 New optimization strategy and protocol needed

  48. Alignment of variables related to neutron skin: =1: full alignment/correlation =0: not aligned P.G. Reinhard W. Nazarewicz in preparation

  49. SciDAC 2 Project:Building a Universal Nuclear Energy Density Functional • Understand nuclear properties “for element formation, for properties of stars, and for present and future energy and defense applications” • Scope is all nuclei, with particular interest in reliable calculations of unstable nuclei and in reactions • Order of magnitude improvement over present capabilities • Precision calculations • Connected to the best microscopic physics • Maximum predictive power with well-quantified uncertainties • [See http://www.scidacreview.org/0704/html/unedf.html • by Bertsch, Dean, and Nazarewicz]

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