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arXiv · 1901.04711

DW Cancri in x-rays

A. A. Nucita·L. Conversi·D. Licchelli
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Abstract

We report on the $XMM$-Newton observation of DW Cnc, a candidate intermediate polar candidate whose historical optical light curve shows the existence of periods at $\simeq 38$, $\simeq 86$ and $\simeq 69$ minutes which were interpreted as the white dwarf spin, the orbital and the spin-orbit beat periodicities. By studying the $0.3-10$ keV light curves, we confirm the existence of a period at $\simeq 38$ minutes and find in the OM light curve a signature for a period at $75\pm 21$ minutes which is consistent with both the orbital and spin-orbit beat. { These findings allow us to unveil without any doubt, the nature of DW Cnc as an accreting intermediate polar. The EPIC and RGS source spectra were analyzed and a best fit model, consisting of a multi-temperature plasma, was found. The maximum temperature found when fitting the data is $kT_{max}\simeq 31$ keV which can be interpreted as an upper limit to the temperature of the shock.

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A. A. Nucita, L. Conversi, D. Licchelli. 2019-01-15. DW Cancri in x-rays. https://doi.org/10.1093/mnras/stz118

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