SIGMA observations of X-ray Nova Velorum 1993 (GRS 1009-45)

P. Goldoni; M. Vargas; A. Goldwurm; P. Laurent; J. -P. Roques; E. Jourdain; J. Malzac; G. Vedrenne; M. Revnivtsev; E. Churazov; M. Gilfanov; R. Sunyaev; A. Dyachkov; N. Khavenson; I. Tserenin; N. Kuleshova

arXiv · astro-ph/9709089

SIGMA observations of X-ray Nova Velorum 1993 (GRS 1009-45)

P. Goldoni·M. Vargas·A. Goldwurm·P. Laurent·J. -P. Roques·E. Jourdain·J. Malzac·G. Vedrenne·M. Revnivtsev·E. Churazov·M. Gilfanov·R. Sunyaev·A. Dyachkov·N. Khavenson·I. Tserenin·N. Kuleshova

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Abstract

We report on hard X-ray observations of X-ray Nova Velorum 1993 (GRS 1009-45) performed with the SIGMA coded mask X-ray telescope in January 1994. The source was clearly detected with a flux of about 60 mCrab in the 40-150 keV energy band during the two observations with a hard spectrum (alpha ~ - 1.9) extending up to ~ 150 keV. These observations confirm the duration of the activity of the source in hard X-rays over 100 days after the first maximum and suggest a spectral hardening which has already been observed in Nova Muscae. These and other characteristics found in these observations strengthen the case for this Nova to be a black hole candidate similar to Nova Muscae.

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P. Goldoni, M. Vargas, A. Goldwurm, P. Laurent, J. -P. Roques, E. Jourdain, J. Malzac, G. Vedrenne, M. Revnivtsev, E. Churazov, M. Gilfanov, R. Sunyaev, A. Dyachkov, N. Khavenson, I. Tserenin, N. Kuleshova. 1997-09-10. SIGMA observations of X-ray Nova Velorum 1993 (GRS 1009-45). https://arxiv.org/abs/astro-ph/9709089

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