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		| Paper: | 
		XMM-Newton Observations of GRB Afterglows | 
	 
	
		| Volume: | 
		312, Third Rome Workshop on Gamma-Ray Bursts in the Afterglow Era | 
	 
	
		| Page: | 
		181 | 
	 
	
		| Authors: | 
		Reeves, J.; Watson, D.; Osborne, J.; O'Brien, P.; Pounds, K. | 
	 
	
	
		| Abstract: | 
		The properties of all 4 GRB X-ray afterglows, observed to date with XMM-Newton, are presented. GRB 011211, GRB010220, and GRB001025A all appear to show X-ray line emission features, whilst a fourth, GRB 020322, shows soft X-ray absorption. The line emission from GRB011211, observed at 11 hours after the initial burst, appears to decay with time, the rest-energies of the lines indicate an outflow of ~ 0.1 c, implying a moderate (days/weeks) time delay between any supernova event and the burst itself. The X-ray spectrum of GRB001025A exhibits a soft excess, which may also be attributable to a blend of emission lines. Overall the observations are supportive of stellar collapse models for GRBs, implying that long GRBs occur in a rich, high density environment. | 
	 
	
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