Photometry and astrometry of SS Leo Minoris during the 2006 October superoutburst

Jeremy Shears; David Boyd; Tom Krajci; Robert Koff; John R. Thorstensen; Gary Poyner

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arXiv · 0707.2206

Photometry and astrometry of SS Leo Minoris during the 2006 October superoutburst

Jeremy Shears·David Boyd·Tom Krajci·Robert Koff·John R. Thorstensen·Gary Poyner

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Abstract

We report unfiltered CCD observations of the first confirmed superoutburst of the SU UMa-type dwarf nova SS LMi in October 2006. From a quiescent magnitude of around 21.7 it rose to 16.2, an outburst amplitude of about 5.5 magnitudes. It declined at 0.17 mag/d for 5 days before slowing to 0.11 mag/d for a further 3 days. The light curve revealed common superhumps with a peak-to-peak amplitude of 0.3 magnitude, which decayed and then re-grew concurrently with the change in decline rate. These were followed by a phase-changing transition to late superhumps. Analysis of these observations has revealed evidence for an orbital period of 0.05572(19) d and a common superhump period of 0.05664(2) d, giving a fractional superhump period excess of 0.017(5). From astrometry of SS LMi in outburst we have established for the first time its correct position as RA 10h 34m 05.85(1)s, Dec +31deg 08m 00.00(18)s (J2000). The position commonly given for SS LMi is that of a nearby star.

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Jeremy Shears, David Boyd, Tom Krajci, Robert Koff, John R. Thorstensen, Gary Poyner. 2007-07-15. Photometry and astrometry of SS Leo Minoris during the 2006 October superoutburst. https://arxiv.org/abs/0707.2206

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