Bibcode
DOI
González Hernández, Jonay I.; Rebolo, Rafael; Israelian, Garik; Harlaftis, Emilios T.; Filippenko, Alexei V.; Chornock, Ryan
Bibliographical reference
The Astrophysical Journal, Volume 644, Issue 1, pp. L49-L52.
Advertised on:
6
2006
Journal
Citations
41
Refereed citations
37
Description
We present medium-resolution optical spectra of the secondary star in
the high Galactic latitude black hole X-ray binary XTE J1118+480 and
determine the abundance of Mg, Al, Ca, Fe, and Ni in its atmosphere. For
all the elements investigated, we find supersolar abundances; thus, we
reject the hypothesis that the black hole came from the direct collapse
of an ancient massive halo star. The compact primary most likely formed
in a supernova event of a massive star whose nucleosynthetic products
polluted the secondary star. The observed element abundances and their
ratios can be explained using a variety of supernova models with a wide
range of metallicities. While an explosive origin in the Galactic halo
or thick disk cannot be discarded, a metal-rich progenitor is clearly
favored by the observed abundance pattern. This suggests that the black
hole was produced in the Galactic thin disk with a violent natal kick,
propelling the X-ray binary to its current location and orbit.