Modelled vs observed abundances of EMP stars

DOI

We compare the elemental abundance patterns of ~200 extremely metal-poor (EMP; [Fe/H]{<}-3) stars to the supernova yields of metal-free stars, in order to obtain insights into the characteristic masses of the first (Population III or Pop III) stars in the universe. The supernova yields are prepared with nucleosynthesis calculations of metal-free stars with various initial masses (M=13, 15, 25, 40 and 100M_{sun}) and explosion energies (E_51=E/10^51^[erg]=0.5-60), to include low-energy, normal-energy, and high-energy explosions. We adopt the mixing-fallback model, to take into account possible asymmetry in the supernova explosions, and the yields that best fit the observed abundance patterns of the EMP stars are searched by varying the model parameters. We find that the abundance patterns of the EMP stars are predominantly best- fitted by the supernova yields with initial masses M<40M_{sun}, and that more than than half of the stars are best-fitted by the M=25M{sun} hypernova (E_51=10) models. The results also indicate that the majority of the primordial supernovae have ejected 10^-2^-10^-1^M_{sun} of ^56^Ni, leaving behind a compact remnant (either a neutron star or a black hole), with a mass in the range of ~1.5-5M{sun}. These results suggest that the masses of the first stars responsible for the first metal enrichment are predominantly <40M{sun}_. This implies that the higher-mass first stars were either less abundant, directly collapsed into a black hole without ejecting heavy elements, or a supernova explosion of a higher-mass first star inhibits the formation of the next generation of low-mass stars at [Fe/H]{<}-3.

Cone search capability for table J/ApJ/857/46/table3 (Best-fit models and observed abundances from literature)

Identifier
DOI http://doi.org/10.26093/cds/vizier.18570046
Source https://dc.g-vo.org/rr/q/lp/custom/CDS.VizieR/J/ApJ/857/46
Related Identifier https://cdsarc.cds.unistra.fr/viz-bin/cat/J/ApJ/857/46
Related Identifier http://vizier.cds.unistra.fr/viz-bin/VizieR-2?-source=J/ApJ/857/46
Metadata Access http://dc.g-vo.org/rr/q/pmh/pubreg.xml?verb=GetRecord&metadataPrefix=oai_b2find&identifier=ivo://CDS.VizieR/J/ApJ/857/46
Provenance
Creator Ishigaki M.N.; Tominaga N.; Kobayashi C.; Nomoto K.
Publisher CDS
Publication Year 2019
Rights https://cds.unistra.fr/vizier-org/licences_vizier.html
OpenAccess true
Contact CDS support team <cds-question(at)unistra.fr>
Representation
Resource Type Dataset; AstroObjects
Discipline Astrophysics and Astronomy; Interdisciplinary Astronomy; Natural Sciences; Observational Astronomy; Physics; Stellar Astronomy