Back to Volume
Paper: Constraints on the Accretion Flow in AE Aquarii from its X-Ray Properties as Observed by ASCA
Volume: 157, Annapolis Workshop on Magnetic Cataclysmic Variables
Page: 343
Authors: Eracleous, Michael
Abstract: AE Aqr is considered today the prototypical magnetic propeller. Interaction of a fragmented accretion flow with the magnetosphere of the rapidly spinning white dwarf is thought to be the cause of the observed large flares. In this paper I present the results of an analysis of archival ASCA X-ray observation of AE Aqr made in 1995 October and discuss the implications for ideas of the flare mechanism. The observation spans about 2 orbital cycles of the binary and includes two flares. The X-ray spectra during flares and during quiescent periods are virtually identical (within uncertainties), save for an increase in flux by a factor of 3 during flares. The spectrum can be modeled as emission from a two-temperature thermal plasma (kT = 0.8 and 3.2 keV). The combined ROSAT and ASCA spectrum can also be modeled in the same fashion, although a three-temperature plasma model is needed for an adequate description (the additional component has kT = 0.15 keV). The main implication of the X-ray spectrum is that the flares have to occur close to the white dwarf so that the available potential energy can heat the X-ray emitting plasma to the observed temperatures.
Back to Volume