INTEGRAL-RXTE observations of Cygnus X-1

K. Pottschmidt; J. Wilms; M. Chernyakova; M. A. Nowak; J. Rodriguez; A. A. Zdziarski; V. Beckmann; P. Kretschmar; T. Gleissner; G. G. Pooley; S. Martinez-Nunez; T. J. -L. Courvoisier; V. Schoenfelder; R. Staubert

doi:10.1063/1.1781011

arXiv · astro-ph/0309203

INTEGRAL-RXTE observations of Cygnus X-1

K. Pottschmidt·J. Wilms·M. Chernyakova·M. A. Nowak·J. Rodriguez·A. A. Zdziarski·V. Beckmann·P. Kretschmar·T. Gleissner·G. G. Pooley·S. Martinez-Nunez·T. J. -L. Courvoisier·V. Schoenfelder·R. Staubert

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Abstract

We present first results from contemporaneous observations of Cygnus X-1 with INTEGRAL and RXTE, made during INTEGRAL's performance verification phase in 2002 November and December. Consistent with earlier results, the 3-250 keV data are well described by Comptonization spectra from a Compton corona with a temperature of kT~50-90 keV and an optical depth of tau~1.0-1.3 plus reflection from a cold or mildly ionized slab with a covering factor of Omega/2pi~0.2-0.3. A soft excess below 10 keV, interpreted as emission from the accretion disk, is seen to decrease during the 1.5 months spanned by our observations. Our results indicate a remarkable consistency among the independently calibrated detectors, with the remaining issues being mainly related to the flux calibration of INTEGRAL.

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K. Pottschmidt, J. Wilms, M. Chernyakova, M. A. Nowak, J. Rodriguez, A. A. Zdziarski, V. Beckmann, P. Kretschmar, T. Gleissner, G. G. Pooley, S. Martinez-Nunez, T. J. -L. Courvoisier, V. Schoenfelder, R. Staubert. 2003-09-06. INTEGRAL-RXTE observations of Cygnus X-1. https://doi.org/10.1063/1.1781011

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