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A Study of the X-Ray Emission of Magnetic Cataclysmic Variable Ae Aquarii

Chul-Sung Choi·Tadayasu Dotani·P. C. Agrawal
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Abstract

We report results from analysis of the X-ray observations of AE Aqr, made with Ginga in June 1988 and with ASCA in October 1995. Pulsations are detected clearly with a sinusoidal pulse profile with periods of $33.076\pm0.001$ s (Ginga) and $33.077\pm0.003$ s (ASCA)\@. The pulse amplitude is relatively small and the modulated flux remains nearly constant despite a factor of 3 change in the average flux during the flare. We reproduce the time-averaged spectrum in the 0.4 -- 10 keV energy band by a thermal emission model with a combination of two different temperatures: kT$_1 = 0.68^{+0.01}_{-0.02}$ keV and kT$_2 = 2.9^{+0.3}_{-0.2}$ keV\@. There is no significant difference between the quiescent and flare energy spectra, although a hint of spectral hardening is recognized during the flare. We interpret these observational results with a model in which AE Aqr is in a propeller stage. Based on this propeller scenario, we suggest that the X-ray emission is originated from magnetospheric radiation.

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Chul-Sung Choi, Tadayasu Dotani, P. C. Agrawal. 1999-09-10. A Study of the X-Ray Emission of Magnetic Cataclysmic Variable Ae Aquarii. https://doi.org/10.1086/307873

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