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The Peculiar 2004 Superoutburst in the Helium Dwarf Nova, 2003aw

D. Nogami·B. Monard·A. Retter·A. Liu·M. Uemura·R. Ishioka·A. Imada·T. Kato
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Abstract

We conducted a time-resolved photometric campaign of the helium dwarf nova, 2003aw in 2004 May--June. 2003aw stayed at 14.7--15.7 mag for the first several days during this campaign, which is the plateau phase of this superoutburst. This variable then rapidly decayed to $\sim$18.0 mag, still brighter by about 2 mag than its quiescence magnitude, and maintained this brightness for about 20 days, having short flares of $\sim$2 mag. A long fading tail followed it. We detected superhumps with a period of 0.02357(4) d [= 2036(3) s] during the plateau phase. The whole light curve of the superoutburst in 2003aw, taking into account the present data and those in the literature, perfectly resembles that of the 1996-1997 superoutburst of the peculiar WZ Sge-type hydrogen-rich dwarf nova, EG Cnc.

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D. Nogami, B. Monard, A. Retter, A. Liu, M. Uemura, R. Ishioka, A. Imada, T. Kato. 2004-09-27. The Peculiar 2004 Superoutburst in the Helium Dwarf Nova, 2003aw. https://doi.org/10.1093/pasj%2F56.6.l39

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