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HV Virginis and WZ Sge-Type Dwarf Novae

Taichi Kato·Yoshiyuki Sekine·Ryuko Hirata
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Abstract

A dwarf nova HV Vir was observed photometrically for eight nights during the outburst in 1992 April - May. The star showed two distinct types of periodic variation: (1) 82.20-min (0.05708 d) double-humped variation with decaying amplitudes during the early stage of the outburst, and (2) 83.80-min (0.05820 d) superhumps in later stages. We attributed the former to "early superhumps", which are only seen in the earliest stage of WZ Sge-type outbursts. The superhump period and evolution of the superhumps, together with general characteristics of the light curve, make HV Vir a typical WZ Sge-type dwarf nova. HV Vir also showed a large increase of the superhump period during the superoutburst. Upon the recognition of the WZ Sge-type nature of an object previously considered as a nova, we present a comprehensive list of candidates for WZ Sge-type dwarf novae, and related systems.

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Taichi Kato, Yoshiyuki Sekine, Ryuko Hirata. 2001-10-09. HV Virginis and WZ Sge-Type Dwarf Novae. https://doi.org/10.1093/pasj%2F53.6.1191

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