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arXiv · 1308.5175

On the nature of CP Pup

Elena Mason·Marina Orio·Koji Mukai·Antonio Bianchini·Domitilla de Martino·Francesco di Mille·Robert E. Williams·Timothy Abbot·Roberto de Propris
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Abstract

We present new X-ray and optical spectra of the old nova CP Pup (nova Pup 1942) obtained with Chandra and the CTIO 4m telescope. The X-ray spectrum reveals a multi-temperature optically thin plasma reaching a maximum temperature of 36$^{+19}_{-16}$ keV absorbed by local complex neutral material. The time resolved optical spectroscopy confirms the presence of the $\sim$1.47 hr period, with cycle-to-cycle amplitude changes, as well as of an additional long term modulation which is suggestive either of a longer period or of non-Keplerian velocities in the emission line regions. These new observational facts add further support to CP Pup as a magnetic cataclysmic variable (mCV). We compare the mCV and the non-mCV scenarios and while we cannot conclude whether CP Pup is a long period system, all observational evidences point at an intermediate polar (IP) type CV.

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Elena Mason, Marina Orio, Koji Mukai, Antonio Bianchini, Domitilla de Martino, Francesco di Mille, Robert E. Williams, Timothy Abbot, Roberto de Propris. 2013-08-23. On the nature of CP Pup. https://doi.org/10.1093/mnras%2Fstt1565

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