Bibcode
González Hernández, Jonay I.
Bibliographical reference
INTERACTING BINARIES: Accretion, Evolution, and Outcomes. AIP Conference Proceedings, Volume 797, pp. 416-421 (2005).
Advertised on:
10
2005
Citations
0
Refereed citations
0
Description
Recent studies of chemical abundances of secondary stars in low mass
X-ray binaries have opened a new window to obtain information on the
progenitors of black holes and neutron stars. Secondary stars could have
captured a significant amount of the ejected matter in the supernova
explosions that originated compact objects in these systems. Thus,
anomalous atmospheric abundances of these stars may be a signature of
nucleosynthetic products in supernovae. The detailed chemical analysis
of secondary stars may provide constraints on many parameters involved
in supernova explosion models like the mass cut, the amount of fallback
matter, possible mixing processes, and explosion energies and
geometries. Such chemical analysis has been made in two black hole
binaries: GRO J1655-40 (Israelian et al. 1999) and A0620-00
(González Hernández et al. 2004) where we have found
several elements enhanced in the secondary stars. These element
abundances compared with element yields in supernova explosion models
suggest that the progenitors of compact objects were massive stars in
the mass range 25-40 Msolar. We have also studied the neutron star
binary Cen X-4 (González Hernández et al. 2005, submitted)
where such strong anomalous abundances, with respect to element
abundances in stars with similar Fe content, have not been found.
However, element abundances appear to be super solar which might be
explained if the secondary could be polluted by the ejected matter (also
containing Fe) in a SN explosion of a progenitor with a He core of
roughly 4 Msolar.