Clustering between high-mass X-ray binaries and OB associations in the Milky Way
Abstract
We present the first direct measurement of the spatial cross-correlation function of high-mass X-ray binaries (HMXBs) and active OB star-forming complexes in the Milky Way. This result relied on a sample containing 79 hard X-ray selected HMXBs and 458 OB associations. Clustering between the two populations is detected with a significance above 7-sigmas for distances < 1 kpc. Thus, HMXBs closely trace the underlying distribution of the massive star-forming regions that are expected to produce the progenitor stars of HMXBs. The average offset of 0.4+-0.2 kpc between HMXBs and OB associations is consistent with being due to natal kicks at velocities of the order of 100+-50 km/s. The characteristic scale of the correlation function suggests an average kinematical age (since the supernova phase) of ~4 Myr for the HMXB population. Despite being derived from a global view of our Galaxy, these signatures of HMXB evolution are consistent with theoretical expectations as well as observations of individual objects.
Keywords
Cite
@article{arxiv.1109.3466,
title = {Clustering between high-mass X-ray binaries and OB associations in the Milky Way},
author = {Arash Bodaghee and John A. Tomsick and Jerome Rodriguez and J. Berian James},
journal= {arXiv preprint arXiv:1109.3466},
year = {2012}
}
Comments
18 pages, 10 figures, 3 tables, accepted for publication in ApJ