Photometry of Three Superoutbursts of the SU UMa-type Dwarf Nova, SW Ursae Majoris

TL;DR

This study analyzed optical photometry of three superoutbursts of SW UMa, revealing consistent superhump evolution, potential residual periodic signals, and the absence of previously observed super-QPOs, suggesting stable binary parameters influence superhump behavior.

Contribution

It provides a comparative analysis of superhump evolution across multiple superoutbursts, highlighting the stability of the process and the absence of super-QPOs in recent observations.

Findings

Superhump evolution was consistent across three superoutbursts.

Residual periodicity was detected after the 2000 superoutburst.

Super-QPOs were not observed in recent superoutbursts.

Abstract

We investigated the superhump evolution, analysing optical photometric observations of the 2000 February-March, the 2002 October-November, and the 2006 September superoutbursts of SW UMa. The superhumps evolved in the same way after their appearance during the 2000 and the 2002 superoutbursts, and probably during the 2006 one. This indicates that the superhump evolution may be governed by the invariable binary parameters. We detected a periodicity in light curve after the end of the 2000 superoutburst without phase shift, which seems to be the remains of the superhumps. We found QPOs at the end stage of the 2000 and the 2002 superoutbursts, but failed to find extraordinarily large-amplitude QPOs called `super-QPOs' which previously have been observed in SW UMa.