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تسجيل مستخدم جديدXMM-Newton observation of the brightest X-ray flare detected so far from SgrA*
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D. Porquet
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We report the high S/N observation on October 3, 2002 with XMM-Newton of the brightest X-ray flare detected so far from SgrA* with a duration shorter than one hour (~ 2.7 ks). The light curve is almost symmetrical with respect to the peak flare, and no significant difference between the soft and hard X-ray range is detected. The overall flare spectrum is well represented by an absorbed power-law with a soft photon spectral index of Gamma=2.5+/-0.3, and a peak 2-10 keV luminosity of 3.6 (+0.3-0.4) x 10^35 erg/s, i.e. a factor 160 higher than the Sgr A* quiescent value. No significant spectral change during the flare is observed. This X-ray flare is very different from other bright flares reported so far: it is much brighter and softer. The present accurate determination of the flare characteristics challenge the current interpretation of the physical processes occuring inside the very close environment of SgrA* by bringing very strong constraints for the theoretical flare models.
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[truncated] In Spring 2007, we observed SgrA* with XMM with a total exposure of ~230ks. We have performed timing and spectral analysis of the new X-ray flares detected during this campaign. To study the range of flare spectral properties, in a consis
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Sgr A*, the compact radio source, believed to be the counterpart of the massive black hole at the galactic nucleus, was observed to undergo rapid and intense flaring activity in X-rays with Chandra in October 2000. We report here the detection with X
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