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Science of rare isotopes: connecting nuclei with the universe Witold Nazarewicz (UTK, ORNL, UWS)

Science of rare isotopes: connecting nuclei with the universe Witold Nazarewicz (UTK, ORNL, UWS) APS Annual Meeting, St. Louis, April 12, 2008. Two take-away messages:

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Science of rare isotopes: connecting nuclei with the universe Witold Nazarewicz (UTK, ORNL, UWS)

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  1. Science of rare isotopes: connecting nuclei with the universe Witold Nazarewicz (UTK, ORNL, UWS) APS Annual Meeting, St. Louis, April 12, 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. Introduction

  3. Some nuclei are more important than others - + - + - + + - + - 149Tb 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 nuclear structure tests of fundamental laws of nature 45Fe applications astrophysics

  4. 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

  5. Radioactive Ion Science Timeline (from RISAC Report) Relativistic Coulomb excitation of 32-Mg at RIKEN Direct radiative capture with 21-Na at ISAC-I 38m-K -correlations at TRINAT 100-Sn discovered at GSI and GANIL Europe Japan First mass measurement of short-lived nuclei at PS in CERN First accelerated beam experiment (13-N) at LLN Two-proton emitters discovered at GSI and GANIL Canada Momentum distribution of halo at RIKEN Z=105 (Db) discovered in Dubna Measurement of half-life of r-process nucleus at Studsvik Mössbauer effect Projectile-fisson of 238-U and Z=112 discovered at GSI Proton emission discovered at Harwell BBHF theory of nucleosynthesis Z=108 chemistry at GSI Acceleration of RIBs at LLN Beta-delayed proton radioactivity discovered at Dubna and McGill Island of inversion at N=20 and shape coexistence in proton-rich Hg at iSOLDE Targeted alpha therapy at ISOLDE ISOLTRAP First ISOL experiment in Copenhagen Laser ion source at ISOLDE Becquerel discovers radioactivity The Curies discover polonium Neutron-induced fission IGISOL at Jyväskylä Isotopic tracer technique by von Hevesy Nobel Prize for magic numbers Nobel Prize for unified model 6-He produced in Copenhagen Explanation of magic numbers RIKEN SPIRAL1 ISOLDE GSI GANIL ISAC-I REX-ISOLDE Nobel Prize for unified model 1900 1930 1960 2000 Parity violation in beta decay Fermi builds controlled fission reactor NSCL HRIBF Shell structure changes in exotic nuclei at ATLAS/HRIBF/NSCL First therapeutic application of artificial radionuclide Nobel Prize for magic numbers Nobel Prize for nucleosynthesis 1940 The Rockefeller Foundation funds the first cyclotron dedicated for biomedical radioisotope production at Washington University in St. Louis. The cyclotron first used radioactive phosphorus for treating leukemia. Invention of PET scanner Trapped francium at Stony Brook Explanation of magic numbers First in-flight separator at Oak Ridge First in-flight fragmentation experiments at Berkeley Radiochemistry used to monitor nuclear weapons tests Shell structure of exotic nuclei with knockout reactions at NSCL 6-He enhanced reaction cross sections at TwinSol beta-NMR demonstrated at ANL Z=100 (Fm) discovered First application of radiochemistry to inertial fusion target diagnosis BBHF theory of nucleosynthesis Studies with accelerated 132-Sn and 82-Ge at HRIBF Neutron halos discovered at Berkeley 21-Na -correlations at Berkeley Measurement of half-life of r-process nucleus at TRISTAN Charge radius of 6-He at ATLAS 78-Ni lifetime at NSCL United States

  6. Science Questions and challenges

  7. Designer Nuclei in Nuclear Landscape superheavy nuclei 225Ra 62Ga 78Ni 134Sn 11Li 283112 45Fe 101Sn 149Tb 68Se Experimental Nuclear Structure @ APS April’08: Baumann (R3.3), Koller (W3.1), Fallon (W3.2) Tanihata (W3.3), H14, M14, R14, X14 82 126 protons terra incognita 50 82 stable nuclei 28 • How do protons and neutrons make stable nuclei and rare isotopes? • What are properties of neutron matter? • What are the heaviest nuclei that can exist? • What is the origin of simple patterns in complex nuclei? 20 50 8 28 known nuclei 2 20 8 2 neutrons

  8. Structure of rare isotopes Old paradigms revisited. Crucial input for theory ANL/Cracow/Manchester/NSCL(2007) 55Ti Digital photography of 45Fe(2p) Warsaw/Tennessee/ORNL/NSCL (2007) 45Fe NSCL (2007) 42Al 43Al 40Mg 1228 No shell closure for N=8,20,28 for drip-line nuclei; new shells at 14,16,32…

  9. 8He … andmass of 11Li: m/m=7·10-8 TRIUMF/GSI (2006) 11Li nuclear radius (fm) 6,8He & 11Li Charge Radii and Masses of Halo NucleiPrecision measurements provide stringent test of nuclear models ANL (2004) T1/2≈ 806 ms ANL/GANIL (2007) T1/2≈ 119ms T1/2≈ 8.6 ms

  10. 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

  11. 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

  12. 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 J. Phys. G 34, R165 (2007)

  13. 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? Thielemann (T3.1) Hans A. Bethe Prize p process s-process L3 S8 r process rp process Nova Neutron star L8 J14 Crust processes T Pyxidis stellar burning protons Calder (E5.2), Frebel (R3.1), Qian (R3.2) Hix (W5.3), D8, H15, J15 neutrons

  14. 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

  15. 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 http://www.jinaweb.org/html/gallery3.html The origin of about half of elements heavier than iron Goes through neutron-rich rare isotopes

  16. - + - + - + + - + - 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

  17. 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)% 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 Half-life Q-value 50Mn,54Co @Jyväskylä (2007) Q=7634.48(7), 8244.54(10) keV Branching Ratio 26mAl,42Sc @Jyväskylä (2006) Q=4232.83(13),6426.13(21) keV • 7 cases (10C,14O,…, 42Sc)measured@CPT/APT(ANL) …stay tuned… • Advances in isospin mixing calculations 38mK

  18. Roadmap for Theory of Nuclei ...provides the guidance Overarching goal: To arrive at a comprehensive microscopic description of all nuclei and low-energy reactions from the the basic interactions between the constituent nucleons • There is no “one size fits all” theory for nuclei, but the theoretical approaches need to be bridged • Main uncertainty: spin-isospin sector. Here, data from rare isotopes are crucial Schmidt (B3.1), Dean (B3.3), Bogner (D4.2), Navratil (D4.3),Charity (X3.1) E14, L14, X15

  19. Ab initio calculations (nuclei, neutron droplets, nuclear matter) • Quantum Monte Carlo (GFMC) 12C • No-Core Shell Model 13C • Coupled-Cluster Techniques 40Ca • Faddeev-Yakubovsky • Bloch-Horowitz • … • Input: • Excellent NN forces based on the phase shift analysis • Chiral NN and NNN potentials based on the effective field theory • Soft interactions obtained from the renormalization group provide low-momentum unification GFMC: S. Pieper 1-2% calculations of A = 6 – 12 nuclear energies are possible excited states with the same quantum numbers computed

  20. Science scales with processors Jaguar Cray XT4@ORNL 11,706 dual-core processor nodes 250 Teraflops after upgrade Blue Gene/P IBM @ANL 8,196 quad-core processor nodes 556 Teraflops after upgrade Example 2: Neutron Drop Calculations • Quantum Monte Carlo for N=14 • Automatic Dynamic Load Balancing • Using 16,384 processors - 97 minutes Speedup efficiency 83% ! Example 1: Large Scale DFT Mass Table Calculations @ • 9,210 nuclei • 599,265 configurations • Using 3,000 processors - about 25 CPU hours Number of processors > number of nuclei! Cycles allocated by DOE's Innovative and Novel Computational Impact on Theory and Experiment (INCITE) program @

  21. Connections and Relevance

  22. Connections to quantum many-body systems Complex Systems • Understanding the transition from microscopic to mesoscopic to macroscopic • Symmetry breaking and emergent phenomena • Quantum chaos • Open quantum systems • Dynamical symmetries and collective dynamics Superfluid Fermionic Systems: The Unitary Gas (Seattle/Warsaw) • Dilute fermion matter: • strongly correlated • very large scattering length • Low-density neutron matter • Cold fermions in traps

  23. Emergent collective behavior in nuclei: Quantum phase transitions 148Sm 152Sm 154Sm Vibrator Rotor Soft Transitional Deformed Spherical Energy Transitional rare isotopes Deformation

  24. Applications of Rare Isotopes How can our knowledge of nuclei and our ability to produce them benefit the humankind? Yttrium Reaction Network W14 • Stockpile stewardship • Required cross sections involve many processes, including (n,), (n,n'), and (n,xn) as well as (p,n), (p,2n) etc.) • Materials science, transmutation of waste, environmental science… • Can we design an economically competitive, energy efficient, reduced-waste nuclear reactor? • Medical and biological research

  25. 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)

  26. 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 divided into 4 groups:

  27. Perspectives

  28. Experiment TRIUMF GSI NSCL GANIL ISOLDE RIKEN HRIBF FRIB Future major facilities Existing major dedicated facilities Funding Opportunity Announced for Establishment of U.S. Facility for Radioactive Ion Beams: DE-PS02-08ER41535 Radioactive Ion Beam Facilities Worldwide …to establish a U.S. Facility for Rare Isotope Beams (FRIB) with forefront scientific research capabilities complimentary to existing or planned facilities world-wide, and to exploit the scientific potential of rare isotope beams…

  29. Theory Connections to computational science EXAMPLE: SCIDAC 2 Universal Nuclear Energy Density Functional • Funded by • Office of Science • ASCR • NNSA • 15 institutions • ~50 researchers • physics • computer science • applied mathematics • foreign collaborators http://unedf.org/ …unprecedented theoretical effort ! 1Teraflop=1012 flops 1peta=1015 flops (next 2-3 years) 1exa=1018 flops (next 10 years) http://www.top500.org/ challenge: utilize leadership class computers

  30. Outlook The study of rare isotopes makes the connection between the Standard Model, complex systems, and the cosmos • Exciting 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 the inter-nucleon interaction, the most reliable theoretical approaches, and the massive use of the computer power available at this moment in time. The prospects are excellent. Thank You

  31. Backup

  32. Nucleonic matter

  33. Nuclear DFT: works well for BE differences S. Cwiok, P.H. Heenen, W. Nazarewicz Nature, 433, 705 (2005) Stoitsov et al., 2008 • Global DFT mass calculations: HFB mass formula: m~700keV

  34. Nuclear Structure: the interaction Effective-field theory (χPT) potentials Vlow-k: can it describe low-energy observables? • Quality two- and three-nucleon interactions exist • Not uniquely defined (local, nonlocal) • Soft and hard-core • The challenge is: • to understand their origin • to understand how to use them in nuclei Bogner, Kuo, Schwenk, Phys. Rep. 386, 1 (2003) N3LO: Entem et al., PRC68, 041001 (2003) Epelbaum, Meissner, et al.

  35. Helium resonances Ab initio: Reactions 5He phase shifts Coupled Clusters GFMC 7Be(p,g)8B, S17 No Core Shell Model

  36. Bimodal fission in nuclear DFT

  37. Synthesis of SHE Observation of fusion enhancement at sub-barrier energies in 134Sn+64Ni (HRIBF, 2007) Loveland (2007): (i) The use of radioactive beams in the synthesis of heavy nuclei can lead to the formation, at reasonable rates, of a group of neutron-rich nuclei not reachable with stable beams. These nuclei are predicted to have longer halflives than existing nuclei. (ii) The best (i.e., highest production rate) reactions for producing these nuclei involve the use of lighter n-rich radioactive beams. (iii) When considering reactions involving radioactive beams, it is important to evaluate the cross section × beam intensity product. (iv) The best way to produce most heavy nuclei, especially those of high Z, is to use stable beams. • ~1000 ions/sec • Probing the influence of neutron excess on fusion at and below the Coulomb barrier • Large sub-barrier fusion enhancement has been observed • Inelastic excitation and neutron transfer play an important role in the observed fusion enhancement

  38. (p,) (,) (,p) (p,) (b+) observable long-lived nuclei Novae: nucleosynthesis up to A ~ 40 mass region T ≤ 4x108 K  ~ 103 g cm-3 27Si 28Si 27Al 24Al 25Al 26Al nova (artist’s impression) rp-process onset 21Mg 22Mg 23Mg 24Mg 25Mg 26Mg 23Na 20Na 21Na 22Na NeNa cycle breakout from HCNO 18Ne 19Ne 20Ne 21Ne 22Ne reaction network for explosive hydrogen burning 17F 18F 19F 14O 15O 16O 17O 18O HCNO 13N 14N 15N (p,) and (,p) reactions on proton-rich nuclei stable 13C 12C unstable

  39. Rare isotope measurements for r-process r-process (d,p) campaign: around 132Sn (HRIBF) 107Zr: halflife Beun, McLaughlin, Surman, Hix 130,132Sn(d,p)131,133Sn 133Sn Zr: neutron branchings r-process (,n) campaign: towards 110Zr (NSCL) New precise masses of neutron-rich nuclei (ANL, ISOLDE, Jyvaskyla, TRIUMF,

  40. Precise masses from Penning TRAP facilities (only selected examples…) from J. Aysto…

  41. Electric Dipole Moment Searches (Time-reversal violation; New Standard Model) - + - + - + + - + - T4 energy 225Ra 1/2- 55.2 keV 0 L 0 R 1/2+ experiment octupole deformation Static octupole deformation can enhance the effect of CP-violating interactions. A handful of such nuclei have been identified over the years, for example 229Pa and 223,225Ra. Such pear-shaped nuclei occur only rarely and only in special regions of the nuclear chart. Theory has confirmed that the size of the EDM (if it exists) is expected to be enhanced in these nuclei compared with 199Hg, the most sensitive stable nucleus presently used in EDM searches, by a factor of several hundred to several thousand.

  42. Radioactive Ion Beam Facilities Timeline 2000 2005 2010 2015 2020 In Flight ISOL Fission+Gas Stopping Beam on target HIE-ISOLDE ISOLDE ISAC-II ISAC-I SPIRAL2 SPIRAL FAIR SIS RIBF RARF NSCL HRIBF CARIBU@ATLAS FRIB

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