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arXiv · 1603.02492

Photometric evolution of the 2016 outburst of recurrent Nova LMC 1968: the first three weeks

U. Munari·F. M. Walter·F. -J. Hambsch·A. Frigo
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Abstract

Optical (BVRI) photometry of the first three weeks of the 2016 outburst of the recurrent Nova LMC 1968 is presented and discussed. The 2016 I-band light-curve is an exact replica, even in the most minute details, of that for the 2010 eruption. The maximum is inferred to have occurred on 2016 Jan 21.2 at I=11.5 mag, corresponding to an absolute magnitude M(I)=-7.15. A ~1 day plateau is present in all bands about six days past optical maximum, simultaneous with the emergence of super-soft X-ray emission in Swift observations, signalling the widespread ionization of the ejecta. The nova entered a much longer plateau about 9 days past maximum, governed by the brightness of the white dwarf, now directly visible and still nuclearly burning on its surface. An outburst recurrence mean period of ~955 days (2.6 yrs) would fit both the OGLE inter-season gaps and the observed intervals between previous outburts.

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U. Munari, F. M. Walter, F. -J. Hambsch, A. Frigo. 2016-03-08. Photometric evolution of the 2016 outburst of recurrent Nova LMC 1968: the first three weeks. https://arxiv.org/abs/1603.02492

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