V446 Herculis (Nova Her 1960) Is an Optical Triple: Implications for the Resumption of Dwarf Nova Outbursts following the Nova

摘要

V446 Her has been reported to have outbursts or flares at a mean interval of ~23 days with an amplitude of ~1.5 mag. This amplitude is quite low for dwarf nova outbursts, which suggests that these events may be due to mass transfer modulations. However, earlier reported photometry included an unrecognized contribution from two additional stars ~3'' away. When corrected for this effect, the amplitude of the outbursts is increased to ~2.5 mag, consistent with the amplitudes of known dwarf novae. Furthermore, it is found that other parameters of the outbursts are consistent with the expected characteristics of dwarf nova events. These parameters include the outburst spacing, the rise and fall times of the outbursts, and variations in outburst amplitude and width. V446 Her is therefore firmly established as a cataclysmic variable that has dwarf nova eruptions in the immediate postnova stage, and is the most unambiguous example of such behavior among the recorded novae.