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		| Paper: | 
		Multiwavelength Modeling the SED of Very Slow Novae PU Vulpeculae and V723 Cassiopeiae | 
	 
	
		| Volume: | 
		490, Stella Novae: Past and Future Decades | 
	 
	
		| Page: | 
		211 | 
	 
	
		| Authors: | 
		Skopal, A. | 
	 
	
	
		| Abstract: | 
		Evolution in the spectrum of very slow novae PU Vul and V723 Cas  during their transition from the optical maximum to the nebular  phase is investigated using the method of disentangling the  composite UV/optical spectra.  Model SEDs suggested that a transient decrease in the WD  luminosity, during the decline from maximum, was caused by  a negative beaming effect, when a neutral disk around the WD  was formed. When the disk disappeared, the luminosity increased  again to values from the beginning of the outburst (in the case  of V723 Cas, at/above the Eddington limit). This suggests the  presence of a mechanism maintaining a high energy output for  a much longer time than it is predicted by the current theories.  Similarity between the lightcurves, but enormous difference of the separation     between the components of PU Vul and V723 Cas binaries suggest      that the mechanism is basically powered by the accretor. | 
	 
	
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