INTEGRAL/RXTE observations of Cygnus X-1

We present results from simultaneous observations of Cyg X‐1 with INTEGRAL and RXTE in 2002 November and December, employing the new RXTE calibration from HEASOFT 5.3. The broad‐band X‐ray/γ‐ray spectrum is well described by Comptonization spectra with an additional reflection component. The temperature of the Comptonizing plasma is kTe ∼ 60–80 keV and its optical depth is τ ∼ 0.8–1.2. The covering factor of the reflector is Ω/2π ∼ 0.1. There is a possible soft excess below 10 keV, interpreted as emission from the accretion disk. The spectral parameters are slightly different from those obtained by us earlier due to the different RXTE‐PCA calibration.