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arXiv · 0905.0348

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

Yuichi Soejima·Daisaku Nogami·Taichi Kato·Makoto Uemura·Akira Imada·Kei Sugiyasu·Hiroyuki Maehara·Ken'ichi Torii·Kenji Tanabe·Arto Oksanen·Kazuhiro Nakajima·Rudolf Novak·Gianluca Masi·Tomas Hynek·Brian Martin·Denis Buczynski·Elena P. Pavlenko·Sergei Yu. Shugarov·Lewis M. Cook
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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.

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Yuichi Soejima, Daisaku Nogami, Taichi Kato, Makoto Uemura, Akira Imada, Kei Sugiyasu, Hiroyuki Maehara, Ken'ichi Torii, Kenji Tanabe, Arto Oksanen, Kazuhiro Nakajima, Rudolf Novak, Gianluca Masi, Tomas Hynek, Brian Martin, Denis Buczynski, Elena P. Pavlenko, Sergei Yu. Shugarov, Lewis M. Cook. 2009-05-04. Photometry of Three Superoutbursts of the SU UMa-type Dwarf Nova, SW Ursae Majoris. https://doi.org/10.1093/pasj%2F61.4.659

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