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

TL;DR

This study presents detailed photometric and astrometric observations of SS LMi during its first confirmed superoutburst, revealing its brightness evolution, superhump behavior, and precise position, contributing valuable data on this dwarf nova.

Contribution

First comprehensive photometric and astrometric analysis of SS LMi's 2006 superoutburst, including orbital and superhump periods and accurate positional data.

Findings

Detected superhumps with 0.3 mag amplitude

Measured orbital period of 0.05572 days

Established SS LMi's precise position for the first time

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.