Integral observation of Cyg X-1 in an intermediate state

J. Malzac; P. O. Petrucci; E. Jourdain; P. Sizun; M. Cadolle; G. Pooley; C. Cabanac; S. Chaty; T. Belloni; J. Rodriguez; J. P. Roques; P. Durouchoux; A. Goldwurm; P. Laurent

arXiv · astro-ph/0411069

Integral observation of Cyg X-1 in an intermediate state

J. Malzac·P. O. Petrucci·E. Jourdain·P. Sizun·M. Cadolle·G. Pooley·C. Cabanac·S. Chaty·T. Belloni·J. Rodriguez·J. P. Roques·P. Durouchoux·A. Goldwurm·P. Laurent

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Abstract

We present preliminary results of an observation of Cygnus X-1 with INTEGRAL performed on June 7-11 2003. Both spectral and variability properties of the source indicate that Cygnus X-1 was in an intermediate state. As expected during state transitions, we find an anticorrelation between the 3-10 keV and the 15 GHz radio fluxes and a strong correlation between the 3-200 keV hardness and radio flux.

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J. Malzac, P. O. Petrucci, E. Jourdain, P. Sizun, M. Cadolle, G. Pooley, C. Cabanac, S. Chaty, T. Belloni, J. Rodriguez, J. P. Roques, P. Durouchoux, A. Goldwurm, P. Laurent. 2004-11-02. Integral observation of Cyg X-1 in an intermediate state. https://arxiv.org/abs/astro-ph/0411069

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