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		| Paper: | 
		The X-ray Variability Properties of PG Quasars: XMM-Newton Results | 
	 
	
		| Volume: | 
		360, AGN Variability from X-Rays to Radio Waves | 
	 
	
		| Page: | 
		123 | 
	 
	
		| Authors: | 
		Guainazzi, M.; Jimenez-Bailon, E.; Piconcelli, E. | 
	 
	
	
		| Abstract: | 
		This paper presents preliminary results of a systematic study of the X-ray spectral variability of PG quasars with XMM-Newton. We concentrate on those objects whose X-ray spectra are well fit in the framework of the “double-Comptonization” model. On short (Δt ~ 103 s) timescales, variability between the soft (E < 2 keV) and the hard (E > 2 keV) bands is uncorrelated. In the two objects, for which observations at different epochs are available, spectral variability in the soft X-ray regime is found. Its timescale is constrained in the range between ~1 week and ~1 year. | 
	 
	
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