X-ray flux and pulse frequency changes of three high mass X-ray binary pulsars: Vela X-1, GX 301-2 and OAO 1657-415

Date

2000-01-01

Author

Inam, SC
Baykal, Altan

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Using archival BATSE (Burst and Transient Source Experiment) 20-50 keV band X-ray flux and pulse frequency time series, we look for correlations between torque, luminosity and specific angular momentum for three high mass X-ray binary pulsars Vela X-1, GX 301-2 and OAO 1657-415. Our results show that there is no correlation between pulse frequency derivative and flux which may be an indication of the absence of stable prograde accretion disk. From the strong correlation of specific angular momentum and torque, we conclude that the accretion geometry changes continuously as suggested by the hydrodynamic simulations (Blondin et al. 1990).

Subject Keywords

X-rays : stars, Stars : pulsars : individual : Vela X1, Stars : pulsars : individual : GX 301-2, Stars : pulsars : individual : OAO 1657-415, Accretion, Accretion disks

URI

https://hdl.handle.net/11511/53893

Journal

ASTRONOMY & ASTROPHYSICS

Collections

Department of Physics, Article

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Citation Formats

S. Inam and A. Baykal, “X-ray flux and pulse frequency changes of three high mass X-ray binary pulsars: Vela X-1, GX 301-2 and OAO 1657-415,” ASTRONOMY & ASTROPHYSICS, pp. 617–623, 2000, Accessed: 00, 2020. [Online]. Available: https://hdl.handle.net/11511/53893.