Observations of Musca X-ray nova with the Art-P telescope onboard "Granat" : precise localization and spectral variability.
Abstract
Data of observations of a 1991 nova in the Musca constellation (GRS1124 - 684) with the ART-P telescope of the Granat observatory, which were obtained during the first seven months after the outburst, are presented. The X-ray nova was localized with an accuracy of better than 1 arcmin, which allowed its optical identification to be confirmed. The source spectrum was similar to X-ray spectra of the well-known black hole candidates but had a steeper (alpha = 2.4) hard tail. The soft luminosity of the source declined during the entire observational period, with an e-folding decay time of about 28 d. According to the ART-P data, the source luminosity decreased by a factor of about 20 in the 8-30 keV band and by a factor of about 120 in the 3-8 keV band during the approximately 200 d of observations. The source did not exhibit significant variability on time scales of minutes and seconds, unlike Cyg X-1 or GS2-23 + 338). In this respect Nova Muscae was similar to Nova Vulpecula (GS2000 + 25).
- Publication:
-
Soviet Astronomy Letters
- Pub Date:
- January 1992
- Bibcode:
- 1992SvAL...18....5G
- Keywords:
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- Novae;
- Stellar Spectra;
- X Ray Sources;
- X Ray Spectroscopy;
- X Ray Stars;
- Light Curve;
- Variability;
- X Ray Astronomy;
- X Ray Telescopes;
- Astrophysics