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Detection of orbital and superhump periods in Nova V2574 Ophiuchi (2004)

Tae W. Kang·Alon Retter·Alex Liu·Mercedes Richards
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Abstract

We present the results of 37 nights of CCD unfiltered photometry of nova V2574 Oph (2004) from 2004 and 2005. We find two periods of 0.14164 d (~3.40 h) and 0.14773 d (~3.55 h) in the 2005 data. The 2004 data show variability on a similar timescale, but no coherent periodicity was found. We suggest that the longer periodicity is the orbital period of the underlying binary system and that the shorter period represents a negative superhump. The 3.40 h period is about 4% shorter than the orbital period and obeys the relation between superhump period deficit and binary period. The detection of superhumps in the light curve is evidence of the presence of a precessing accretion disk in this binary system shortly after the nova outburst. From the maximum magnitude - rate of decline relation, we estimate the decay rate t_2 = 17+/-4 d and a maximum absolute visual magnitude of M_Vmax = -7.7+/-1.7 mag.

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Tae W. Kang, Alon Retter, Alex Liu, Mercedes Richards. 2005-12-22. Detection of orbital and superhump periods in Nova V2574 Ophiuchi (2004). https://doi.org/10.1086/500088

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