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Home , Nuclear astrophysics

THE ENERGY OF

NUCLEAR

THE ORIGIN OF THE ELEMENTS

Stellar Origin of Energy the Elements

Nuclear Astrophysics

Astrophysics Nuclear ROBERT D’ESCOURT ATKINSON (1931)

1942 β

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

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

Salpeter

Hoyle (1954) 1957 : B2FH

n from (,n) on 4N+1 nuclei 1957 : B2FH 1957 : A. G. W. CAMERON Nuclear reactions in stars and nucleogenesis

Hayashi (1950) n,p equilibrium

X(n)/X(p)~0.13 at freeze-out

X(He-4)~2 X(n) ~0.25 Primordial Spite and Spite 1982 -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

Nuclear reaction rates, and resulting WMAP abundances, depend on baryon density Dark baryons SBBN: Non

2 missing matter baryonic

L U M I N O U S B A R Y O N S N O Y R A B S U O N I MU L

problems dark E R T T A M G N I T A T I V A R G matter

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

1971 LiBeB production and in the galaxy with full treatment of GCR composition and propagation and stellar sources for Li (NP 2012)

Stellar processes CNO of GCR always the same (from rotating massive stars)

Most Li from stars for (AGB, ) but PRIMARY required yields production ~10 times larger of Be and B than theory

NP 2012

Hoyle and Fowler 1960 Explosive nucleosynthesis What powers the lightcurves of supernovae ?

B2FH

Be-7 : Borst 1950 Cf-254: Baade, B2FH and Christy 1956 Ni-56 : T. Pankey Jr 1963

Clayton, Colgate, Fishman 1969 Clayton, 70ies: yields of radioactivities

Assuming that their decay produces the solar -ray line lightcurves of SNIa abundances of their stable daughter nuclei But he missed Al-26 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 10000 SNII and WR stars Nucleosynthesis still active in the Galaxy

Tueller et al. 1989 The 847 keV line of Co56 was detected NOT from a SNIa, but from SN1987A (18 M⊙ 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 THE ONION-SKIN Clayton and MODEL Woosley 1974

Hoyle 1955

Also:

Iben 1962+ Paczynski 1968+ Ikeuchi 1970+ Arnett 1970+

Ikeuchi, Hayashi et al. 1971

Clayton et al. 1961

Identification of different neutron exposures for the s-abundance curve Termination of the s-process Kappeler et al. 1999

Straniero et al. 2009 Arlandini et al. 1999

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

The observed universality of the r-process abundances

contrasts with the increased scatter of r/Fe at low metallicities

Cowan et al. 2013 Large dispersion of X/Fe for elements heavier than Fe peak (s- or r-) Sr Ba Eu

Frebel 2010 -4 -3 -2 -1 [Fe/H]

Argast et al. 2004 NS mergers appear later than CCSN

in TIME

But… what about Core collapse Supernovae METALLICITY ? mergers (high frequency, low r- yield) (low frequency, high r- yield)

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 !) Age_vs metallicity

Galactic Chemical Evolution ingredients

Stellar properties Lifetimes of stars (Myr) (function of mass M and metallicity Z) - Lifetimes - Yields (quantities of elements ejected) - Masses of residues (WD, NS, BH)

Collective Stellar Properties - Star Formation Rate (SFR) Initial Mass Function - Initial Mass Function (IMF) He3, He4, N14, C12 to Fe-peak, C12, C13, O17, weak s-, r-, p- F19, s- Gas Flows

- Infall INTERMEDIATE MASSIVE - Outflow MASS - Radial inflows in disks LOW MASS PN SN Solar Neighborhood Constraints:

Local column densities of gas, stars, SFR

as well as

O/Fe vs Fe/H Age – Metallicity (uncertain)

Metallicity distribution (requires slow infall) Age - Metallicity Metallicity distribution O/Fe vs Fe/H (requires SNIa for late Fe) 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. 1999

Full treatment of GCR composition, propagation and nucleosynthesis for LiBeB 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 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 yields (amounts of elements ejected) Stellar yields vary widely with stellar mass

A lot for products of early hydrostatic burning phases

Unknown for elements E(SN)=1051 erg M(Ni56)=0.1 M⊙ near the mass-cut

Yield ratios may vary considerably

BUT the average over the IMF is always close to solar ! Observed Calculated Abundances [X/Fe] in metal poor stars of the halo

α ? Primary ! α α

α α α

α ? 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

Suppose that we routinely obtain CCSN explosions. Would this imply that we understand them ? Importance of data compilations Nuclear reaction rates Exp. Thermonucl.: Caughlan+Fowler+: 1967, 1975, 1983, 1988 NACRE I: 1999, II: 2014 Solar system abundances Semi-empirical Holmes+Wooley+Fowler: 1976 BRUSLIB 1937: Goldsmith Tsao+Silberberg 1974 (spallation) Non-SMOKER 1949: Brown n-captures: 1956: Suess-Urey Macklin+Gibbons: 1961, 1965 1973: Cameron Bao+Kappeler +: 1987, 2000 1982: Anders-Ebihara β-decays 1989: Anders-Grevesse Takahashi+Yokoi: 1987 1993: Grevesse-Sauval-Noels 2003: Lodders Massive star yields 2005: Asplund-Grevesse-Sauval 1995 Arnett Z⊙ 2-32 (He) Elm

1995 WW Z-dep 11-40 M⊙ Isot. H-Zn Z⊙ = 0.0134 from 0.02 1995 TNH Z⊙ 13-25 Isot. H-Ge 1998 PCB Z-dep 6-120 ML Sel. Isot. 2004 CL Z-dep 15-35 Isot. H-Ge 2006 Nomoto+ Z-dep 13-70 Isot. C-Zn 2006 MM+ Z-dep 9_120 ML,Rot Sel. Isot. 2013 CL Z⊙ 13-120 ML,Rot Isot. H-Mo Dust Globular cluster composition AGB, C-stars, Novae, X-bursts s-stars, WR, … Galactic Pre- Nucleo  Chemical solar -ray cosmo LIM stars SN Types grains chronology Massive stars Lightcurves evolution SN remnants Convection, Stable nuclei Radioactive Mass loss Hydro 1-2-3D, -induced GCR Metallicity GR, EOS, n-captures, fission properties Solar  Rotation, … -transport, … Thermonuclear Solar model Advanced phases Supernovae Hydrostatic Explosive Nuclear properties: masses, decay rates, reaction cross-sections Stellar Photometry Stellar, ISM spectroscopy 3K MWB GCR spectra Stellar Physics Cosmology physics H-burn : Main Seq 3-α: Red giants Stellar Primordial Spallogenic Stellar Energy Origin of the Elements Nuclear Astrophysics Astrophysics