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20-100 keV properties of cataclysmic variables detected in the INTEGRAL/IBIS survey

E. J. Barlow·C. Knigge·A. J. Bird·A. J. Dean·D. J. Clark·A. B. Hill·M. Molina·V. Sguera
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Abstract

Analysis of INTEGRAL/IBIS survey observations has revealed that the rare intermediate polar and asynchronous polar cataclysmic variables are consistently found to emit in the 20-100 keV energy band, whereas synchronous polars and the common non-magnetic CVs rarely do so. From the correlation of a candidate INTEGRAL/IBIS survey source list with a CV catalogue, 15 CV detections by IBIS have been established including a new INTEGRAL source IGR J06253+7334. The properties of these sources and 4 additional CV candidates are discussed in the context of their 20-100 keV emission characteristics and we conclude that the INTEGRAL mission is an important tool in the detection of new magnetic CV systems. Furthermore, analysis of the time-averaged spectra of CVs detected by INTEGRAL indicate that although there is little difference between the spectral slopes of the different sub-types, intermediate polars may be considerably more luminous than polars in the soft gamma-ray regime. We also present the detection of an unusual high-energy burst from V1223 Sgr discovered by inspection of the IBIS light-curve. Additionally, we have compared the IBIS and optical AAVSO light-curves of SS Cyg and extracted IBIS spectra during single periods of optical outburst and quiescence. We find that the 20-100 keV flux is an order of magnitude greater during optical quiescence. This is in agreement with previous studies which show that the hard X-ray component of SS Cyg is suppressed during high accretion states

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E. J. Barlow, C. Knigge, A. J. Bird, A. J. Dean, D. J. Clark, A. B. Hill, M. Molina, V. Sguera. 2006-07-20. 20-100 keV properties of cataclysmic variables detected in the INTEGRAL/IBIS survey. https://doi.org/10.1111/j.1365-2966.2006.10836.x

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