THE ENERGY OF STARS NUCLEAR ASTROPHYSICS THE ORIGIN OF THE ELEMENTS

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1 THE ENERGY OF STARS NUCLEAR ASTROPHYSICS THE ORIGIN OF THE ELEMENTS

2 Stellar Energy Origin of the Elements Nuclear Astrophysics Astrophysics Nuclear Physics

3 ROBERT D ESCOURT ATKINSON (1931)

5 1942

6 β MeV n-capture cross-sections from declassified data (Hughes 1946)

G. Gamow (mid-40ies): all elements produced in the hot primordial Universe (Big Bang) by

Hoyle (mid-40ies): all elements produced Inside stars during their pre-collapse stage, by

(metals) than the younger stellar population (Population I) of the galactic disk Chamberlain and

8 G. Gamow (mid-40ies): all elements produced in the hot primordial Universe (Big Bang) by successive neutron captures F. Hoyle (mid-40ies): all elements produced Inside stars during their pre-collapse stage, by thermonuclear reactions Old stars of galactic halo (Population II) contain less heavy elements (metals) than the younger stellar population (Population I) of the galactic disk Chamberlain and Aller 1951 The chemical composition of the Milky Way was substantially different in the past Existence of chemically peculiar stars WR stars, Carbon stars Tc in s-stars (Merill 1952).

10 Salpeter Hoyle

11 (1954)

12 1957 : B2FH n from (,n) on 4N+1 nuclei

13 1957 : B2FH

14 1957 : A. G. W. CAMERON Nuclear reactions in stars and nucleogenesis

17 Hayashi (1950) n,p equilibrium X(n)/X(p)~0.13 at freeze-out X(He-4)~2 X(n) ~0.25

18 L U M I N O U S B A R Y O N S G R A V I T A T I N G M A T T E R Primordial Nucleosynthesis -Only way to produce so much He4 ( 25 % by mass) -Only way to produce Deuterium (destroyed in stars) -Only way to produce so much early Li7 Theoretical abundances agree with observations perfectly for D, satisfactorily for He-4, poorly for Li-7 Spite and Spite 1982 Nuclear reaction rates, and resulting abundances, depend on baryon density SBBN: 2 missing matter problems Dark baryons WMAP Non baryonic dark matter

order as spallation cross sections of CNO LiBeB: σ(b) > σ(li) > σ(be) LiBeB is

20 GCR composition is heavily enriched in Li, Be, B (a factor ~10 6 for Be and B) Solar composition: X(Li) > X(B) > X (Be) GCR composition: X(B) > X(Li) > X(Be) Same order as spallation cross sections of CNO LiBeB: σ(b) > σ(li) > σ(be) LiBeB is produced by spallation of CNO as GCR propagate in the Galaxy (Reeves, Fowler, Hoyle 1970) 1971

21 LiBeB production and evolution in the galaxy with full treatment of GCR composition and propagation and stellar sources for Li (NP 2012) Stellar processes Most Li from stars (AGB, nova) but required yields ~10 times larger than theory CNO of GCR always the same (from rotating massive stars) for PRIMARY production of Be and B NP 2012

23 Hoyle and Fowler 1960 Explosive nucleosynthesis

24 What powers the lightcurves of supernovae? B2FH Be-7 : Borst 1950 Cf-254: Baade, B2FH and Christy 1956 Ni-56 : T. Pankey Jr 1963

27 Clayton, Colgate, Fishman 1969 Clayton, 70ies: yields of radioactivities -ray line lightcurves of SNIa Assuming that their decay produces the solar abundances of their stable daughter nuclei But he missed Al-26

28 First -ray line from radioactivity: 1.8 MeV from Al26 ( 1 Myr) (Mahoney et al. 1982) COMPTEL/CGRO legacy(circa 2000) Diffuse emission from 2 M /Myr of Al26, produced from SNII and WR stars Nucleosynthesis still active in the Galaxy Tueller et al The 847 kev line of Co56 was detected NOT from a SNIa, but from SN1987A (18 M star in LMC, at 50 kpc) Confirmation of explosive nucleosynthesis (stable Fe-56 is produced as unstable Ni-56) Radioactivity powers the late lightcurves of supernovae Line seen 6 months earlier than expected! Hydrodynamic instabilities mix the SN interior

29 THE ONION-SKIN MODEL Clayton and Woosley 1974 Hoyle 1955

31 Also: Iben Paczynski Ikeuchi Arnett 1970+

32 Ikeuchi, Hayashi et al. 1971

34 Clayton et al Identification of different neutron exposures for the s-abundance curve Termination of the s-process

35 Kappeler et al. 1999

37 Straniero et al. 2009

38 Arlandini et al Reproducing the Solar s-only distribution in a parametrized stellar environment and the observed heavy element distribution in low metallicity halo stars Bisterzo et al. 2010

40 The observed universality of the r-process abundances contrasts with the increased scatter of r/fe at low metallicities Cowan et al. 2013

41 Large dispersion of X/Fe for elements heavier than Fe peak (s- or r-) Sr Ba Eu Frebel [Fe/H] Argast et al NS mergers appear later than CCSN in TIME But what about METALLICITY? Core collapse Supernovae (high frequency, low r- yield) Neutron star (low frequency, mergers high r- yield)

44 A first stellar generation of massive stars only To produce a lot of black holes (= DARK MATTER!) and to avoid having too many long-lived low-mass stars of low metallicity (= G-DWARF problem!)

45 Age_vs metallicity

47 Galactic Chemical Evolution ingredients Stellar properties (function of mass M and metallicity Z) Lifetimes of stars (Myr) - Lifetimes - Yields (quantities of elements ejected) - Masses of residues (WD, NS, BH) Collective Stellar Properties - Star Formation Rate (SFR) - Initial Mass Function (IMF) Gas Flows Initial Mass Function He3, He4, N14, C12, C13, O17, F19, s- C12 to Fe-peak, weak s-, r-, p- - Infall - Outflow - Radial inflows in disks LOW MASS INTERMEDIATE MASS PN MASSIVE SN

48 Solar Neighborhood Constraints: Local column densities of gas, stars, SFR as well as Age Metallicity (uncertain) O/Fe vs Fe/H Metallicity distribution (requires slow infall) O/Fe vs Fe/H (requires SNIa for late Fe) Age - Metallicity Metallicity distribution

49 X/X at T-4.5 Gyr Yields of massive stars Woosley-Weaver 1995 Yields of LIM stars Van den Hook and Groenewegen 1997 Yields of SNIa Iwamoto et al Full treatment of GCR composition, propagation and nucleosynthesis for LiBeB

50 Yields of massive stars Most abundant nuclei ejected by a star of 25 M (WW95) Thickness of layers depends on assumptions about convection and mixing processes Abundances in each layer depend on adopted nuclear reaction rates Abundances in inner layers depend also on explosion mechanism Overall structure/evolution also depends on rotation, mass loss etc. Large uncertainties still affecting the supernova yields (amounts of elements ejected)

51 Stellar yields vary widely with stellar mass A lot for products of early hydrostatic burning phases Unknown for elements near the mass-cut E(SN)=10 51 erg M(Ni56)=0.1 M Yield ratios may vary considerably BUT the average over the IMF is always close to solar!

52 Observed Calculated

53 Abundances [X/Fe] in metal poor stars of the halo α? Primary! α α α α α α?

54 Chemical evolution from C to Zn : theory vs observations Woosley-Weaver 95 Chieffi-Limongi 04 ALSO Van den Hoek and Groenewegen 1997 for IMS and Iwamoto et al 1997 for SNIa

57 Suppose that we routinely obtain CCSN explosions. Would this imply that we understand them?

58 Solar system abundances 1937: Goldsmith 1949: Brown 1956: Suess-Urey 1973: Cameron 1982: Anders-Ebihara 1989: Anders-Grevesse 1993: Grevesse-Sauval-Noels 2003: Lodders 2005: Asplund-Grevesse-Sauval Z = from 0.02 Importance of data compilations Nuclear reaction rates Exp. Thermonucl.: Caughlan+Fowler+: 1967, 1975, 1983, 1988 NACRE I: 1999, II: 2014 Semi-empirical Holmes+Wooley+Fowler: 1976 Tsao+Silberberg 1974 (spallation) n-captures: Macklin+Gibbons: 1961, 1965 Bao+Kappeler +: 1987, 2000 β-decays Takahashi+Yokoi: 1987 Massive star yields BRUSLIB Non-SMOKER 1995 Arnett Z 2-32 (He) Elm 1995 WW Z-dep M Isot. H-Zn 1995 TNH Z Isot. H-Ge 1998 PCB Z-dep ML Sel. Isot CL Z-dep Isot. H-Ge 2006 Nomoto+ Z-dep Isot. C-Zn 2006 MM+ Z-dep 9_120 ML,Rot Sel. Isot CL Z ML,Rot Isot. H-Mo

Solar AGB, C-stars, s-stars, WR, LIM stars Massive stars Convection, Mass loss Metallicity Rotation, Dust Novae, X-bursts SN Types Lightcurves SN remnants Hydro 1-2-3D, GR, EOS, -transport, Solar

59 Solar AGB, C-stars, s-stars, WR, LIM stars Massive stars Convection, Mass loss Metallicity Rotation, Dust Novae, X-bursts SN Types Lightcurves SN remnants Hydro 1-2-3D, GR, EOS, -transport, Solar model Advanced phases Supernovae Globular cluster composition Galactic Chemical evolution Stable nuclei Presolar grains -induced n-captures, fission Thermonuclear Hydrostatic Nuclear properties: masses, decay rates, reaction cross-sections Stellar Photometry Stellar, ISM spectroscopy 3K MWB -ray astronomy Radioactive Explosive Stellar Physics Cosmology Cosmic ray physics H-burn : Main Seq 3-α: Red giants Stellar Primordial Spallogenic Stellar Energy Origin of the Elements Nuclear Astrophysics Astrophysics Nuclear Physics Nucleo cosmo chronology GCR properties GCR spectra

ON THE CHEMICAL EVOLUTION OF THE MILKY WAY. The Metallicity distribution of the halo in the hierarchical merging paradigm

ON THE CHEMICAL EVOLUTION OF THE MILKY WAY The Metallicity distribution of the halo in the hierarchical merging paradigm Halo abundance patterns and stellar yields Standard chemical evolution of solar