The radial velocity of the companion star in the low-mass X-ray binary 2S 0921-630: limits on the mass of the compact object

Details The radial velocity of the companion star in the low-mass X-ray binary 2S 0921-630: limits on the mass of the compact object The radial velocity of the companion star in the low-mass X-ray binary 2S 0921-630: limits on the mass of the compact object

2004-10-06

arxiv.org/abs/astro-ph/0410151v1

Mon.Not.Roy.Astron.Soc. 356 (2005) 621-626

Astronomy and Astrophysics

Astrophysics

6 pages, 3 figures, accepted for publication in MNRAS

Scientific paper

10.1111/j.1365-2966.2004.08476.x

In this Paper we report on optical spectroscopic observations of the low-mass X-ray binary 2S 0921-630 obtained with the Very Large Telescope. We found sinusoidal radial velocity variations of the companion star with a semi-amplitude of 99.1+-3.1 km s^-1 modulated on a period of 9.006+-0.007 days, consistent with the orbital period found before for this source, and a systemic velocity of 44.4+-2.4 km s^-1. Due to X-ray irradiation the centre-of-light measured by the absorption lines from the companion star is likely shifted with respect to the centre-of-mass. We try to correct for this using the so-called K-correction. Conservatively applying the maximum correction possible and using the previously measured rotational velocity of the companion star, we find a lower limit to the mass of the compact object in 2S 0921-630 of M_X sin^3 i > 1.90+-0.25 Msun (1 sigma errors). The inclination in this system is well constrained since partial eclipses have been observed in X-rays and optical bands. For inclinations between 60< i<90 degrees we find 1.90+-0.25

Affiliated with

Also associated with

No associations

Rating

The radial velocity of the companion star in the low-mass X-ray binary 2S 0921-630: limits on the mass of the compact object 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 The radial velocity of the companion star in the low-mass X-ray binary 2S 0921-630: limits on the mass of the compact object, we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and The radial velocity of the companion star in the low-mass X-ray binary 2S 0921-630: limits on the mass of the compact object will most certainly appreciate the feedback.

Rate now

Comments { 0 }

Profile ID: LFWR-SCP-O-169508