ASTROPHYSICAL JOURNAL, cilt.449, sa.1, 1995 (SCI-Expanded)
We present X-ray observation of the old nova CP Puppis obtained by the ROSAT Position Sensitive Proportional Counter in 1993 April. The source 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 thermal bremsstrahlung emission model with temperature greater than or equal to 1 keV. The X-ray count rates are modulated with the previously known spectroscopic period similar to 0(d).0614 ( similar to 88.4 minutes) of the system at the 3 sigma confidence level. The hard X-ray flux and the detected X-ray modulations suggest that CP Puppis is an intermediate polar system.