Chemical Abundances of the Secondary Star in the Black Hole X-ray Binary XTE J1118+480

Details Chemical Abundances of the Secondary Star in the Black Hole X-ray Binary XTE J1118+480 Chemical Abundances of the Secondary Star in the Black Hole X-ray Binary XTE J1118+480

2008-01-31

arxiv.org/abs/0801.4936v1

Astronomy and Astrophysics

Astrophysics

Accepted for publication in the Astrophysical Journal

Scientific paper

10.1086/586888

Following the recent abundance measurements of Mg, Al, Ca, Fe, and Ni in the black hole X-ray binary XTE J1118+480 using medium-resolution Keck II/ESI spectra of the secondary star (Gonz\'alez Hern\'andez et al. 2006), we perform a detailed abundance analysis including the abundances of Si and Ti. These element abundances, higher than solar, indicate that the black hole in this system formed in a supernova event, whose nucleosynthetic products could pollute the atmosphere of the secondary star, providing clues on the possible formation region of the system, either Galactic halo, thick disk, or thin disk. We explore a grid of explosion models with different He core masses, metallicities, and geometries. Metal-poor models associated with a formation scenario in the Galactic halo provide unacceptable fits to the observed abundances, allowing us to reject a halo origin for this X-ray binary. The thick-disk scenario produces better fits, although they require substantial fallback and very efficient mixing processes between the inner layers of the explosion and the ejecta, making quite unlikely an origin in the thick disk. The best agreement between the model predictions and the observed abundances is obtained for metal-rich progenitor models. In particular, non-spherically symmetric models are able to explain, without strong assumptions of extensive fallback and mixing, the observed abundances. Moreover, asymmetric mass ejection in a supernova explosion could account for the required impulse necessary to launch the system from its formation region in the Galactic thin disk to its current halo orbit.

Affiliated with

Also associated with

No associations

Rating

Chemical Abundances of the Secondary Star in the Black Hole X-ray Binary XTE J1118+480 does not yet have a rating. At this time, there are no reviews or comments for this scientific paper.

If you have personal experience with Chemical Abundances of the Secondary Star in the Black Hole X-ray Binary XTE J1118+480, we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and Chemical Abundances of the Secondary Star in the Black Hole X-ray Binary XTE J1118+480 will most certainly appreciate the feedback.

Rate now

Comments { 0 }

Profile ID: LFWR-SCP-O-204845