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arXiv · astro-ph/0308395

First INTEGRAL observations of Cygnus X-3

O. Vilhu·L. Hjalmarsdotter·A. A. Zdziarski·A. Paizis·M. L. McCollough·V. Beckmann·T. J. -L. Courvoisier·K. Ebisawa·P. Kretschmar·P. Goldoni·N. J. Westergaard·P. Hakala·D. Hannikainen
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Abstract

We present the first INTEGRAL results on Cyg X-3 from the PV phase observations of the Cygnus region. The source was clearly detected by the JEM-X, ISGRI and SPI detectors. The INTEGRAL observations were supported by simultaneous pointed RXTE observations. Their lightcurves folded over the 4.8 hour binary period are compatible with the mean RXTE/ASM and CGRO/BATSE light curves. We fit our broad band X-ray/Gamma-ray spectra with a physical model, which represents the first such published model for Cyg X-3. The main physical processes in the source are thermal Comptonization and Compton reflection with parameters similar to those found for black-hole binaries at high Eddington rates.

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O. Vilhu, L. Hjalmarsdotter, A. A. Zdziarski, A. Paizis, M. L. McCollough, V. Beckmann, T. J. -L. Courvoisier, K. Ebisawa, P. Kretschmar, P. Goldoni, N. J. Westergaard, P. Hakala, D. Hannikainen. 2003-08-22. First INTEGRAL observations of Cygnus X-3. https://doi.org/10.1051/0004-6361%3A20031257

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