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IW And is a Z Cam-Type Dwarf Nova

T. Kato·R. Ishioka·M. Uemura
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Abstract

IW And was discovered as a unique blue variable, which spends 72% of time in "inactive" state, and was only occasionally observed in bright or faint states. Although the past spectroscopy confirmed that the object is a cataclysmic variable (CV), the object has been regarded as significantly different from the known subclasses of CVs. We observed IW And on 55 nights between 2001 December 6 and 2002 March 25. These observations clearly indicate that the object is a Z Cam-type dwarf nova. The duty cycle of standstill in IW And is exceptionally high among Z Cam stars. IW And is apparently the first object to fill the gap between classical Z Cam stars and novalike (NL) stars.

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T. Kato, R. Ishioka, M. Uemura. 2002-04-20. IW And is a Z Cam-Type Dwarf Nova. https://arxiv.org/abs/astro-ph/0204353

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