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arXiv · 1108.1287

Swift observations of the March 2011 outburst of the cataclysmic variable NSV 1436: a probable dwarf nova (Research Note)

J. P. Osborne·K. L. Page·A. A. Henden·J. -U. Ness·M. F. Bode·G. J. Schwarz·S. Starrfield·J. J. Drake·E. Kuulkers·A. P. Beardmore
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Abstract

The March 2011 outburst of the poorly-studied cataclysmic variable NSV 1436 offered an opportunity to decide between dwarf nova and recurrent nova classifications. We use seven daily observations in the X-ray and UV by the Swift satellite, together with AAVSO V photometry, to characterise the outburst and decline behaviour. The short optical outburst coincided with a faint and relatively soft X-ray state, whereas in decline to fainter optical magnitudes the X-ray source was harder and brighter. These attributes, and the modest optical outburst amplitude, indicate that this was a dwarf nova outburst and not a recurrent nova. The rapid optical fading suggests an orbital period below 2 hours.

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J. P. Osborne, K. L. Page, A. A. Henden, J. -U. Ness, M. F. Bode, G. J. Schwarz, S. Starrfield, J. J. Drake, E. Kuulkers, A. P. Beardmore. 2011-08-05. Swift observations of the March 2011 outburst of the cataclysmic variable NSV 1436: a probable dwarf nova (Research Note). https://doi.org/10.1051/0004-6361/201117088

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