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arXiv · 1312.5039

NuSTAR and Swift observations of the fast rotating magnetized white dwarf AE Aquarii

Takao Kitaguchi·Hongjun An·Andrei M. Beloborodov·Eric V. Gotthelf·Takayuki Hayashi·Victoria M. Kaspi·Vikram R. Rana·Steven E. Boggs·Finn E. Christensen·William W. Craig·Charles J. Hailey·Fiona A. Harrison·Daniel Stern·Will W. Zhang
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Abstract

AE Aquarii is a cataclysmic variable with the fastest known rotating magnetized white dwarf (P_spin = 33.08 s). Compared to many intermediate polars, AE Aquarii shows a soft X-ray spectrum with a very low luminosity (L_X ~ 10^{31} erg/s). We have analyzed overlapping observations of this system with the NuSTAR and the Swift X-ray observatories in September of 2012. We find the 0.5-30 keV spectra to be well fitted by either an optically thin thermal plasma model with three temperatures of 0.75 +0.18 -0.45, 2.29 +0.96 -0.82, and 9.33 +6.07 -2.18 keV, or an optically thin thermal plasma model with two temperatures of 1.00 +0.34 -0.23 and 4.64 +1.58 -0.84 keV plus a power-law component with photon index of 2.50 +0.17 -0.23. The pulse profile in the 3-20 keV band is broad and approximately sinusoidal, with a pulsed fraction of 16.6 +/- 2.3%. We do not find any evidence for a previously reported sharp feature in the pulse profile.

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Takao Kitaguchi, Hongjun An, Andrei M. Beloborodov, Eric V. Gotthelf, Takayuki Hayashi, Victoria M. Kaspi, Vikram R. Rana, Steven E. Boggs, Finn E. Christensen, William W. Craig, Charles J. Hailey, Fiona A. Harrison, Daniel Stern, Will W. Zhang. 2013-12-18. NuSTAR and Swift observations of the fast rotating magnetized white dwarf AE Aquarii. https://doi.org/10.1088/0004-637x%2F782%2F1%2F3

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