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Theory for Nuclear Processes in Stars and Nucleosynthesis Theory for nuclear processes in stars and nucleosynthesis Gabriel Martínez Pinedo Nuclear Astrophysics in Germany November 15-16, 2016 Nuclear Astrophysics Virtual Institute Ab-initio description of nuclear reactions Weak processes in stars r process nucleosynthesis Outline 1 Ab-initio description of nuclear reactions 2 Weak processes in stars 3 r process nucleosynthesis Ab-initio description of nuclear reactions Weak processes in stars r process nucleosynthesis Ab-initio description of nuclear reactions Extending ab-initio approaches for a proper treatment of continuum. Cluster phenomena in light nuclei (Hoyle state) Different approaches available. Fermion Molecular Dynamics No-Core Shell Model with Continuum Nuclear Lattice Dohet-Eraly, et al, PLB 757, 430 (2016) Ab-initio description of nuclear reactions Weak processes in stars r process nucleosynthesis Stellar electron capture and beta-decay We need to account for a broad range of conditions Stellar evolution and accretion phases. Sensitive to relatively few reactions: URCA pairs 23Na-23Ne, 25Mg-25Na,...for white dwarfs and heavier nuclei neutron star crust. Accurate modeling of individual transitions, important screening corrections. Explosive phases. Type Ia supernova, Oxygen deflagration in ONe cores. Competition between many electron capture and beta-decay processes. Core-collapse: core evolution sensitive to electron capture on exotic neutron rich nuclei. Ab-initio description of nuclear reactions Weak processes in stars r process nucleosynthesis Range of nuclei for Oxygen deflagration many of the relevant rates are based on simple analytical estimates (ANA). Figure from Sam Jones Ab-initio description of nuclear reactions Weak processes in stars r process nucleosynthesis Electron captures during collapse Most relevant electron capture nuclei during collapse e 50 (b) 50 28 40 = N Z 30 28 82 Proton Number log &[(e | 20 20 10 50 '# '$ '% 20 30 4050 60 70 80 90 Neutron Number Sullivan et al., ApJ 816, 44 (2015) Mainly nuclei around N = 50 and N = 82. Sensitive to shell structure far from stability. Theoretical challenge: description of correlations across shell closures. Many of the relevant nuclei are becoming experimentally accessible. Ab-initio description of nuclear reactions Weak processes in stars r process nucleosynthesis Neutrino-matter interactions in supernova Ref. run 80 0.58 + weak magn. + wm + n decay 0.56 60 e 0.54 Y /baryon] 40 B S 0.52 S [k Ye 20 0.5 0.48 0 0.5 1 2 3 5 10 t − tbounce [s] Many different processes contributing during different phases: explosion, neutron star deleptonization. Consistent treatment with underlying experimentally constrained EoS. Code implementations often introduce errors of order the claimed accuracy. What is their role in mergers? Ab-initio description of nuclear reactions Weak processes in stars r process nucleosynthesis Neutrino nucleus reactions Having accurate neutrino spectra is also GT: (3He; t), Zegers+ 2006; Forbidden: RPA 26 26 Mg + ν Al + e− -1 important for the production of several e → 10 7 11 19 26 nuclei ( Li, B, F, including Al). 3 10 ) -2 10 ) 2 V m e c 2 M 2 10 4 2 − 1 0 1 = ( -3 ® n 10 ν o i 1 E t 28 ­ c 10 ( Si e ν s f s 2 ν s o -4 E r c GT and Fermi transitions (data) 10 100 Including forbidden transitions (RPA) Transitions to bound states, experimental Transitions to bound states 10-1 10-5 (ν,ν'np) 0 10 20 30 40 50 60 Neutrino energy (MeV) low: hEνe i = 8:8 MeV, hEν¯e i = hEνµ,τ i = 12:6 MeV 26 27 Al (ν,ν' n) Al high: hEνe i = hEν¯e i = 12:6 MeV, hEνµ,τ i = 18:9 MeV 20 KEPLER high energies ) ¯ 15 low energies M (ν 5 without ν e − ,e 0 - 1 ( 10 ) d (p,γ) l e i y l A 6 5 2 25 26Mg Mg 0 15 20 25 30 Main sequence mass (M ) A. Sieverding ¯ Ab-initio description of nuclear reactions Weak processes in stars r process nucleosynthesis Making Gold in Nature: r-process nucleosynthesis 250 Known mass Known half−life r−process waiting point (ETFSI−Q) 100 200 98 96 94 92 90 88 Solar r abundances 86 84 188 190 186 82 80 78 184 180 182 76 178 176 74 164 166 168 170 172 174 150 72 162 70 160 N=184 68 158 66 156 154 64 152 150 62 140 142 144 146 148 1 60 138 134 136 58 130 132 0 128 10 56 54 126 124 10 −1 52 122 The r-process requires the knowledge of 120 50 116 118 10 −2 48 112 114 110 46 −3 108 10 100 106 N=126 44 104 the properties of extremely 100 102 42 10 98 96 40 92 94 38 88 90 86 84 r−process path 36 82 neutron-rich nuclei: 34 80 78 32 74 76 30 72 70 28 66 68 64 26 62 N=82 28 60 30 32 34 36 38 40 42 44 46 48 50 52 54 56 58 Nuclear masses. Beta-decay half-lives. Neutron capture rates. Fission rates and yields. Ab-initio description of nuclear reactions Weak processes in stars r process nucleosynthesis r process in dynamical ejecta from mergers Ejection of very neutron-rich material in mergers results in abundance distributions insensitive to variations of astrophysical conditions. Sensitivity to nuclear physics input remains. FRDM WS3 10-3 10-4 10-5 10-6 abundances at 1 Gyr 10-7 10-8 HFB21 DZ31 10-3 10-4 10-5 10-6 abundances at 1 Gyr 10-7 10-8 120 140 160 180 200 220 240 120 140 160 180 200 220 240 mass number, A mass number, A Mendoza-Temis, Wu, Langanke, GMP, Bauswein, Janka, PRC 92, 055805 (2015) Ab-initio description of nuclear reactions Weak processes in stars r process nucleosynthesis Theoretical masses far from stability Theoretical models do rather well far from stability! Sn (Z=50) Isotopes Mumpower + 2016 Spread due to small differences in symmetry energy (∼ 0:5 MeV, smaller experimental range 29.0-32.7). Ab-initio description of nuclear reactions Weak processes in stars r process nucleosynthesis Comparison S 2n Very similar predictions for Q-values (relevant quantity). 15 FRDM DZ31 WS3 HFB 27 AME 2012 10 (MeV) 2n S 5 Sn (Z=50) Isotopes 0 70 75 80 85 90 95 100 105 110 Neutron Number Variations in localized regions responsible for different abundances predictions. Ab-initio description of nuclear reactions Weak processes in stars r process nucleosynthesis Outlook: addressing systematic diff. between mass models Most of the differences between mass models originate due to: Treatment of transitional nuclei (shape coexistence). Requires beyond mean field techniques (Rodríguez+ 2015) Proper description odd and odd-odd nuclei. (3) ∆ (N) = (S n(N + 1) − S n(N))=2 A. Arzhanov, Gogny functional Sn (Z = 50) Isotopes 1.8 1.5 Sn 1.6 50 1.4 1.0 1.2 [MeV] (MeV) (3) n (3) ∆ 1 Pert. QP ∆ FRDM Pert. T−Odd 0.5 DZ31 0.8 Equal Filling WS3 Full Blocking HFB 27 0.6 AME12 AME 2012 45 50 55 60 65 70 75 80 85 90 50 55 60 65 70 75 80 85 90 Number of Neutrons Neutron Number Ab-initio description of nuclear reactions Weak processes in stars r process nucleosynthesis Constraining neutron capture rates Liddick, et al., Phys. Rev. Lett. 116, 242502 (2016) 5 10 10-5 (b) 69Ni(n, ) 70 Ni rate (c) (a) 7 10 BRUSLIB 104 JINA REACLIB ) -6 1- 10 lo 3 10 ms -1 -3 1 - 6 3 10 2 -7 m 10 10 c( x > (E ) (MeV ) f(E ) (MeV ) 10 <N 10-8 A 105 1 -9 10-1 10 -1 0 1 2 3 4 5 6 7 0 2 4 6 8 10 12 14 16 18 10 1 T(109 K) Ex (MeV) E (MeV) Experimental constrains in gamma-strength far from stability. Understanding low energy upbend and behaviour with neutron excess. Extending reaction model beyond statistical treatment. Ab-initio description of nuclear reactions Weak processes in stars r process nucleosynthesis Global beta-decay calculations Marketin & GMP 2016 120 Beta-decay rates determine the speed of 110 100 -3 -2 -1 0 +1 +2 +3 matter flow from light to heavy nuclei. 90 80 70 r-process path determined by neutron 60 50 separation energies 40 proton number D3C∗ FRDM 30 log10 T1/2 /T1/2 20 nuclei with largest impact are those with 10 00 00 20 40 60 80 100 120 140 160 180 200 220 240 larger instantaneous half-lives. neutron number Despite tremendous progress at RIB facilities (RIBF at RIKEN) most of the half-lives are based on theoretical Mustonen & Engel 2016 calculations. Two microscopic calculations (GT+FF) have become available: Covariant density functional theory + QRPA (Marketin+ 2016) Skyrme finite-amplitude method (Mustonen & Engel 2016) Ab-initio description of nuclear reactions Weak processes in stars r process nucleosynthesis Fission barriers The impact of different fission barriers and yields has not been sufficiently explored. Goriely & GMP 2015 S. Giuliali Giuliani et al 2016 Goriely et al 2007 Möller et al 2009 Ab-initio description of nuclear reactions Weak processes in stars r process nucleosynthesis Kilonova light curve Understanding the nuclear physics signatures in kilonova light curves 1041 ) 40 1 10 − 1039 (ergs s 1038 bol L 1037 FRDM (Beta-decay dominates) DZ31 (Alpha-decay dominates) 1036 0 5 10 15 20 25 30 Days Ratio of luminosities at peak value and at late times can be used to constrain the produced amount of nuclei between Pb and U. Barnes, Kasen, Wu, GMP, ApJ 829, 110 (2016)..
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