Photometric study of new southern SU UMa‐type dwarf novae and candidates – III. NSV 10934, MM Sco, AB Nor and CAL 86

Kyoto University, Kioto, Kyoto, Japan
Monthly Notices of the Royal Astronomical Society (Impact Factor: 5.11). 12/2003; 347(3):861 - 872. DOI: 10.1111/j.1365-2966.2004.07271.x
Source: arXiv


We photometrically observed four southern dwarf novae in outburst (NSV 10934, MM Sco, AB Nor and CAL 86). NSV 10934 was confirmed
to be an SU UMa-type dwarf nova with a mean superhump period of 0.07478(1) d. This star also showed transient appearance of
quasi-periodic oscillations during the final growing stage of the superhumps. Combined with the recent theoretical interpretation
and with the rather unusual rapid terminal fading of normal outbursts, NSV 10934 may be a candidate intermediate polar showing
SU UMa-type properties. The mean superhump periods of MM Sco and AB Nor were determined to be 0.06136(4) and 0.08438(2) d,
respectively. We suggest that AB Nor belongs to a rather rare class of long-period SU UMa-type dwarf novae with low mass-transfer
rates. We also observed an outburst of the suspected SU UMa-type dwarf nova CAL 86. We identified this outburst as a normal
outburst and determined the mean decline rate of 1.1 mag d−1.

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