Period derivative of the M15 X-ray Binary AC211/X2127+119
Astrophysics
2009-10-30 v1
Abstract
We have combined Rossi X-ray Timing Explorer observations of X2127+119, the low-mass X-ray binary in the globular cluster M15, with archival X-ray lightcurves to study the stability of the 17.1 hr orbital period. We find that the data cannot be fit by the Ilovaisky (1993) ephemeris, and requires either a 7sigma change to the period or a period derivative Pdot/P~9x10e-7 per year. Given its remarkably low L_X/L_opt such a Pdot lends support to models that require super-Eddington mass transfer in a q~1 binary.
Cite
@article{arxiv.astro-ph/9808323,
title = {Period derivative of the M15 X-ray Binary AC211/X2127+119},
author = {L. Homer and P. A. Charles},
journal= {arXiv preprint arXiv:astro-ph/9808323},
year = {2009}
}
Comments
11 pages, 3 figures, to be published in New Astronomy