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New Chances for Nuclear Astrophysics. Interdisciplinary research improved: observations astrophysical models nuclear theory NUCLEAR DATA. On the shoulders of giants. The Presence. The Foundation. Nuclear Physics at the eve of a new era. UNDERGROUND LABS (from LUNA to DUSEL)
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New Chances for Nuclear Astrophysics • Interdisciplinary research • improved: • observations • astrophysical models • nuclear theory • NUCLEAR DATA
On the shoulders of giants The Presence The Foundation
Nuclear Physics at the eve of a new era • UNDERGROUND LABS • (from LUNA to DUSEL) • RADIOACTIVE ION-BEAMS • (from Louvain, Isolde .... via ISAC, ORNL... towards RIKEN, FRIB, FAIR) • Nuclear Models • (from phenomenology to ab-initio)
Fermionic Molecular Dynamics - Structure 17Ne 20Ne 22Ne • Realistic effective interaction (Unitary Correlation Operator Method) • Microscopic description of light nuclei using nucleons as degrees of freedom • Consistent description of shell structure, clusters, halos • Connection to experiment: spectra, electromagnetic and weak transitions, densities, form factors, spectroscopic amplitudes Gabriel Martínez Pinedo - ENNA: Theory
Fermionic Molecular Dynamics - Reactions Scattering states 3He(,)7Be FMD Data Gabriel Martínez Pinedo - ENNA: Theory
Radioactive-ion beams: Claus other Love From Parksville, Geneve, Louvain To RIKEN, FRIB, FAIR ISAC, RIKEN, FRIB, FAIR
Each heavy atom in our body was build and processed through ~100-1000 star generations since the initial Big Bang event! We are made of star stuff Carl Sagan
Signatures of Nucleosynthesis solar abundance distribution • nucleosynthesis processes • nucleosynthesis history • of our universe The stellar abundance distribution is a reflection of nuclear structure and nuclear stability!
Simulation of Supernova Collapse • Electron capture on nuclei • Composition: increasingly neutron rich nuclei • Elastic neutrino scattering on nuclei Courtesy: RIKEN
Effects of Nuclear Electron Capture during Core Collapse The electron capture at high densities results in lower Ye and generates neutrino wind which is necessary for driving the shock. Hix, Messer, Mezzacappa, et al ‘03 Electron captures on nuclei dominate
Two-Dimensional Supernova Simulation • Plasma instabilities • Equation of State • Neutrino transport • Neutrino opacities • Dense matter correlations • Neutrino-nucleon reactions • Rotation, magnetic fields..... Courtesy: Hans-Thomas Janka Courtesy Hans-Thomas Janka courtesy
Explosive Nucleosynthesis Neutrino reactions with nucleons determine the proton-to-neutron ratio • Neutrino-Proton Process • (early ejecta, proton rich) • R-Process • (late ejecta, neutron rich)
The R-Process • Masses • Half lives • Neutron capture rates • Fission • Neutrino reactions Courtesy: K.-L. Kratz
TRIUMF/ISAC future (2010-2018) New proton spallation beam line on UC (p,)/()/(p,)/(,p) reactions for novae/XRB/SNII more power for spallation e.g. 18Ne(,p), 30P(p,), 25Al(p,), 17F(p,), 11C(p,), 13N(p,),,…. AND new target stations for more target & ion source development). Photo-fission on U-target Neutron-rich studies: (d,p) for (n,) using EMMA/TIGRESS/SHARC, TITAN mass measurements for Sn, Q and TIGRESS structure studies of r-process nuclei, N=82 closed shell. 3 RIB in parallel New isotopes & more target and source developments. MORE experiments
RIKEN RI Beam Factory (RIBF) Experiment facility To be funded In phase II Old facility Accelerator RIPS SHE (eg. Z=113) GARIS 60~100 MeV/nucleon ~5 MeV/nucleon RILAC SCRIT AVF ZeroDegree SAMURAI fRC RRC SLOWRI SRC IRC RI-ring SHARAQ BigRIPS CRIB (CNS) 350-400 MeV/nucleon New facility • Intense (80 kW max.) H.I. beams (up to U) of 345AMeV at SRC • Fast RI beams by projectile fragmentation and U-fission at BigRIPS • Operation since 2007
World’s First and Strongest K2600MeV Superconducting Ring Cyclotron SRC 400 MeV/u Light-ion beam 345 MeV/u Uranium beam BigRIPS World’s Largest Acceptance 9 Tm Superconducting RI beam Separator ~250-300 MeV/nucleon RIB K980-MeV Intermediate stage Ring Cyclotron (IRC)
Search for new neutron-rich isotopes using a 345 A MeV 238U beam at the BigRIPS in-flight separator • I = 0.02 pnA • Two new isotopes : 125, 126Pd (Onishi et al, JPSJ 77 (08)083201.) • I=0.2 pnA • More than 20 new isotopes • including an r-process nucleus 128Pd (Onishi et al., in preparation) BigRIPS The first half of BigRIPS (F0-F2) : radioactive beam productions The second half of BigRIPS (F3-F7): particle identification of beams in the Br-DE-TOF method High resolution in A/Q determination 0.04% for Z=26.
FRIB will constrain weak interactions in supernovae How do supernovae explode? Electron capture and beta decay rates play important role in Core collapse supernovae Dynamics of collapse Shock energetics Thermonuclear supernovae Nucleosynthesis Flame propagation 2.1. Energy in stellar explosions: Weak interactions in supernovae Need data to constrain and develop nuclear theory NSCL measurements by R. Zegers et al.
FRIB Capability to Address r-Process 82 Asymmetry dependenceof fission barriers (d,p) for (n,g) 50 N=126 126 NSCL experimentsincluding 78Ni RISACbench-mark 82 (70) Yb Known b-decay (69) Tm (68) Er 28 FRIBreach (67) Ho FRIB reach forb-decay properties (66) Dy 50 Masses
Solar System r-process Abundance Pattern today Existing facilities FRIB+ FAIR+RIKEN RIA A colored dot means that the relevant nuclear data (mass, halflife, P(βn)) could be measured. At present except in a few cases (blue) can output of models be matched to measured abundances. The next generation exotic beam facilities will allow one to • constrain r-process theories using abundance data • extract full information about r-process (and its environment) fromobservational data
R-Process Simulation Courtesy: Gabriel Martinez-Pinedo
FAIR Chance: Nuclear masses • R-Process abundances depend on neutron separation energies • Different mass models predict different patterns • FRDM: ‚robust‘ patterns, as observed in old halo stars in Milky Way • ETFSI: individual patterns strongly depending on neutron-to-seed ratios
Competition velocity of ejected matter vs. halflives IF halflives were known, strong constraint of matter ejection from neutron star surface! FAIR Chance: Role of Halflives
FAIR Chance: Neutron Stars • Neutron Stars are laboratories for matter at extreme densities • Neutron rich nuclei • Equation of State for nuclear matter • Exotic phases?
Neutron star surface Radiativecooling Nuclearreactions H,He gas thermonuclear ashes ocean thermonuclear outer crust Electroncapture Innercrust pycnonuclear n cooling Fate of ashes on neutron star surface
106Pd rp-ashes 4.8 x 1011 g/cm3 106Ge 56Fe 1.8 x 1012 g/cm3 68Ca Increase with Z1Z2 2.5 x 1011 g/cm3 72Ca 4.4 x 1012 g/cm3 56Ar 1.5 x 1012 g/cm3 34Ne Crust processes Ouellette, Gupta & Brown 2005 Haensel & Zdunik 1990, 2003 Beard & Wiescher 2003 Known mass superbursts
Relay of Nuclear Astrophysics The Son The Grandson The Father
Relay of Nuclear Astrophysics The Son The Grandson The Father Must be the hair and the beard!!