GZ Cancri : a cataclysmic variable at the lower edge of the period gap ⋆

نویسندگان

  • C. Tappert
  • A. Bianchini
چکیده

We present calibrated photometry and time-resolved spectroscopy of the cataclysmic variable GZ Cnc. Radial velocities of the Hα emission line reveal an orbital period of 0.08825(28) d, or 2.118(07) h, placing the system at the lower edge of the period gap. One of our observations catches the system on the rise to an overlooked, possibly small-amplitude, outburst. At certain phases during this stage the profiles of the emission lines are distorted by a high velocity absorption component. We discuss this phenomenon in the context of the recent suggestion that the long-term lightcurve of GZ Cnc resembles those of intermediate polars.

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تاریخ انتشار 2003