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Cataclysmic variables from a ROSAT/2MASS selection I: Four new intermediate polars

B. T. Gaensicke·T. R. Marsh·A. Edge·P. Rodriguez-Gil·D. Steeghs·S. Araujo-Betancor·E. Harlaftis·O. Giannakis·S. Pyrzas·L. Morales-Rueda·A. Aungwerojwit
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Abstract

We report the first results from a new search for cataclysmic variables (CVs) using a combined X-ray (ROSAT) / infrared (2MASS) target selection that discriminates against background AGN. Identification spectra were obtained at the Isaac Newton Telescope for a total of 174 targets, leading to the discovery of 12 new CVs. Initially devised to find short-period low-mass-transfer CVs, this selection scheme has been very successful in identifying new intermediate polars. Photometric and spectroscopic follow-up observations identify four of the new CVs as intermediate polars: 1RXSJ063631.9+353537 (Porb~201min, Pspin=1008.3408s or 930.5829), 1RXSJ070407.9+262501 (Porb~250min, Pspin=480.708s), 1RXSJ173021.5-055933 (Porb=925.27min, Pspin=128.0s), and 1RXSJ180340.0+401214 (Porb=160.21min, Pspin=1520.51s). RXJ1730, also a moderately bright hard X-ray source in the INTEGRAL/IBIS Galactic plane survey, resembles the enigmatic AE Aqr. It is likely that its white dwarf is not rotating at the spin equilibrium period, and the system may represent a short-lived phase in CV evolution.

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B. T. Gaensicke, T. R. Marsh, A. Edge, P. Rodriguez-Gil, D. Steeghs, S. Araujo-Betancor, E. Harlaftis, O. Giannakis, S. Pyrzas, L. Morales-Rueda, A. Aungwerojwit. 2005-04-21. Cataclysmic variables from a ROSAT/2MASS selection I: Four new intermediate polars. https://doi.org/10.1111/j.1365-2966.2005.09138.x

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