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arXiv · 0812.4420

The very short supersoft X-ray state of the classical nova M31N 2007-11a

M. Henze·W. Pietsch·G. Sala·M. Della Valle·M. Hernanz·J. Greiner·V. Burwitz·M. J. Freyberg·F. Haberl·D. H. Hartmann·P. Milne·G. G. Williams
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Abstract

Short supersoft X-ray source (SSS) states (durations < 100 days) of classical novae (CNe) indicate massive white dwarfs that are candidate progenitors of supernovae type Ia. We carry out a dedicated optical and X-ray monitoring program of CNe in the bulge of M 31. We discovered M31N 2007-11a and determined its optical and X-ray light curve. We used the robotic Super-LOTIS telescope to obtain the optical data and XMM-Newton and Chandra observations to discover an X-ray counterpart to that nova. Nova M31N 2007-11a is a very fast CN, exhibiting a very short SSS state with an appearance time of 6-16 days after outburst and a turn-off time of 45-58 days after outburst. The optical and X-ray light curves of M31N 2007-11a suggest a binary containing a white dwarf with a mass greater than one solar mass.

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M. Henze, W. Pietsch, G. Sala, M. Della Valle, M. Hernanz, J. Greiner, V. Burwitz, M. J. Freyberg, F. Haberl, D. H. Hartmann, P. Milne, G. G. Williams. 2009-04-28. The very short supersoft X-ray state of the classical nova M31N 2007-11a. https://doi.org/10.1051/0004-6361%2F200811581

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