  GZ Cnc was discovered as a variable star by Takamizawa (Tmz V34), which
turned out to a cataclysmic variable (CV). Past studies have shown that this
object is a good candidate for a rarely outbursting, long-period dwarf nova.
Only three outbursts were recorded between 1999 and 2001. In 2002 March-May,
the object suddenly showed a dramatic increase of the outburst frequency. The
shortest observed interval was only 11 d. We suggest that the present behavior
may be interpreted as a clustering of short outbursts occasionally seen in
intermediate polars (magnetic CVs). The present activity can also be comparable
to V426 Oph, another dwarf nova which is known to show occasionally increased
activities. The resemblances in the X-ray properties and the outburst behavior
suggests that GZ Cnc and V426 Oph may comprise a new class of (weakly magnetic)
cataclysmic variables.
