ROSAT OBSERVATION OF THE OLD CLASSICAL NOVA CP PUPPIS

We present X-ray observation of the old nova CP Puppis obtained by the ROSAT Position Sensitive Proportional Counter in 1993 April. The sour ce is detected with a count rate of 0.067 +/- 0.004 counts s(-1). The total observed X-ray flux between 0.1 and 2.4 keV is similar to 3 X 10 (-12) ergs s(-1) cm(-2). The spectrum of the source is best fit by a t hermal bremsstrahlung emission model with temperature greater than or equal to 1 keV. The X-ray count rates are modulated with the previousl y known spectroscopic period similar to 0(d).0614 ( similar to 88.4 mi nutes) of the system at the 3 sigma confidence level. The hard X-ray f lux and the detected X-ray modulations suggest that CP Puppis is an in termediate polar system.