Observations of the X-Ray Afterglows of GRB 011211 and GRB 001025 by [ITAL]XMM-Newton[/ITAL]

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Abstract
We present the results of observations of the X-ray afterglow emission of the gamma-ray bursts GRB011211 and GRB001025 by XMM-Newton. For GRB011211 XMM detected fading X-ray object with an average flux in 0.2-10 keV fading out from 2.7 x 10(-11) erg/sq.cm/s during the first 5 ks of 27-ks observation to 1.0 x 10(-13) erg/sq.cm/s toward the end of the observation. The spectrum of the afterglow can be fit to power law with alpha=2.14+/-0.03 and Galactic absorption value. This Crab-like spectrum is typical for GRB afterglows. No significant evolution of spectral parameters has been detected during the observation. Similar X-ray spectrum with alpha=2.01+/-0.09 has been observed by the XMM from the GRB001025. The non-detection of any extra absorption in these spectra above the Galactic value is an interesting fact and may impose restrictions to the favorable GRB models involving burst origin in star-forming regions