M33 X-7: ChASeM33 reveals the first eclipsing black hole X-ray binary
Pietsch W, Haberl F, Sasaki M, Gaetz TJ, Plucinsky PP, Ghavamian P, Long KS, Pannuti T (2006)
Publication Status: Published
Publication Type: Journal article
Publication year: 2006
Journal
Publisher: UNIV CHICAGO PRESS
Book Volume: 646
Pages Range: 420-428
Journal Issue: 1
Abstract
The first observations conducted as part of the Chandra ACIS survey of M33 (ChASeM33) sampled the eclipsing X-ray binary M33 X-7 over a large part of the 3.45 day orbital period and have resolved eclipse ingress and egress for the first time. The occurrence of the X-ray eclipse allows us to determine an improved ephemeris of mid-eclipse and binary period as HJD (2; 453; 639.119 +/- 0.005) +/- N(3.453014 +/- 0.000020) and constrain the eclipse half-angle to 26 degrees.5 +/- 1 degrees.1. There are indications for a shortening of the orbital period. The X-ray spectrum is best described by a disk blackbody spectrum typical for black hole X-ray binaries in the Galaxy. We find a flat power density spectrum, and no significant regular pulsations were found in the frequency range of 10(-4) to 0.15 Hz. HST WFPC2 images resolve the optical counterpart, which can be identified as an O6 III star with the help of extinction and color corrections derived from the X-ray absorption. Based on the optical light curve, the mass of the compact object in the system most likely exceeds 9 M-circle dot. This mass, the shape of the X-ray spectrum, and the short-term X-ray time variability identify M33 X-7 as the first eclipsing black hole high-mass X-ray binary.
Authors with CRIS profile
Involved external institutions
Max-Planck-Institut für extraterrestrische Physik (MPE) / Max Planck Institute for Extraterrestrial Physics
Germany (DE)
Space Telescope Science Institute (STScI)
United States (USA) (US)
Morehead State University
United States (USA) (US)
Johns Hopkins University (JHU)
United States (USA) (US)
Harvard-Smithsonian Center for Astrophysics (CfA)
United States (USA) (US)
Germany (DE)
Space Telescope Science Institute (STScI)
United States (USA) (US)
Morehead State University
United States (USA) (US)
Johns Hopkins University (JHU)
United States (USA) (US)
Harvard-Smithsonian Center for Astrophysics (CfA)
United States (USA) (US)
How to cite
APA:
Pietsch, W., Haberl, F., Sasaki, M., Gaetz, T.J., Plucinsky, P.P., Ghavamian, P.,... Pannuti, T. (2006). M33 X-7: ChASeM33 reveals the first eclipsing black hole X-ray binary. Astrophysical Journal, 646(1), 420-428.
MLA:
Pietsch, Wolfgang, et al. "M33 X-7: ChASeM33 reveals the first eclipsing black hole X-ray binary." Astrophysical Journal 646.1 (2006): 420-428.
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