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arXiv · 1111.3804

Quasi-periodic flares in EXO 2030+375 observed with INTEGRAL

D. Klochkov·C. Ferrigno·A. Santangelo·R. Staubert·P. Kretschmar·I. Caballero·K. Postnov·C. A. Wilson-Hodge
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Abstract

Context: Episodic flaring activity is a common feature of X-ray pulsars in HMXBs. In some Be/X-ray binaries flares were observed in quiescence or prior to outbursts. EXO 2030+375 is a Be/X-ray binary showing "normal" outbursts almost every ~46 days, near periastron passage of the orbital revolution. Some of these outbursts were occasionally monitored with the INTEGRAL observatory. Aims: The INTEGRAL data revealed strong quasi-periodic flaring activity during the rising part of one of the system's outburst. Such activity has previously been observed in EXO 2030+375 only once, in 1985 with EXOSAT. (Some indications of single flares have also been observed with other satellites.) Methods: We present the analysis of the flaring behavior of the source based on INTEGRAL data and compare it with the flares observed in EXO 2030+375 in 1985. Results: Based on the observational properties of the flares, we argue that the instability at the inner edge of the accretion disk is the most probable cause of the flaring activity.

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D. Klochkov, C. Ferrigno, A. Santangelo, R. Staubert, P. Kretschmar, I. Caballero, K. Postnov, C. A. Wilson-Hodge. 2011-11-16. Quasi-periodic flares in EXO 2030+375 observed with INTEGRAL. https://doi.org/10.1051/0004-6361%2F201118185

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