The X-ray Pulse Profile of BG CMi

Abstract

We present an analysis of the X-ray data of a magnetic cataclysmic variable, BG CMi, obtained with ROSAT in March 1992 and with ASCA in April 1996. We show that four peaks clearly exist in the X-ray pulse profile, unlike a single peak found in the optical profile. The fluxes of two major pulses are $\sim 2 - 5$ times larger than those of two minor pulses. The fraction of the total pulsed flux increases from 51% to 85% with increasing energy in 0.1 $-$ 2.0 keV, whereas it decreases from 96% to 22% in 0.8 $-$ 10 keV. We discuss the implications of our findings for the origin of the pulse profile and its energy dependence.

To appear in New Astronomy