SPI/INTEGRAL observation of the Cygnus region

L. Bouchet; E. Jourdain; J. -P. Roques; P. Mandrou; P. von Ballmoos; S. Boggs; P. Caraveo; M. Cassé; B. Cordier; R. Diehl; P. Durouchoux; A. von Kienlin; J. Knödlseder; P. Jean; P. Leleux; G. Lichti; J. Matteson; F. Sanchez; S. Schanne; V. Schönfelder; G. Skinner; A. Strong; B. Teegarden; G. Vedrenne; C. Wunderer

doi:10.1051/0004-6361:20031324

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SPI/INTEGRAL observation of the Cygnus region

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Abstract

We present the analysis of the first observations of the Cygnus region by the SPI spectrometer onboard the Integral Gamma Ray Observatory, encompassing ${\sim}$ 600 ks of data. Three sources namely Cyg X-1, Cyg X-3 and EXO 2030+375 were clearly detected. Our data illustrate the temporal variability of Cyg X-1 in the energy range from 20 keV to 300 keV. The spectral analysis shows a remarkable stability of the Cyg X-1 spectra when averaged over one day timescale. The other goal of these observations is SPI inflight calibration and performance verification. The latest objective has been achieved as demonstrated by the results presented in this paper.

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L. Bouchet, E. Jourdain, J. -P. Roques, P. Mandrou, P. von Ballmoos, S. Boggs, P. Caraveo, M. Cassé, B. Cordier, R. Diehl, P. Durouchoux, A. von Kienlin, J. Knödlseder, P. Jean, P. Leleux, G. Lichti, J. Matteson, F. Sanchez, S. Schanne, V. Schönfelder, G. Skinner, A. Strong, B. Teegarden, G. Vedrenne, C. Wunderer. 2003-10-15. SPI/INTEGRAL observation of the Cygnus region. https://doi.org/10.1051/0004-6361%3A20031324

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