V1432 Aql: A polar or an intermediate polar?

¹ Department of Astronomy & Astrophysics, Tata Institute of Fundamental Research, Homi Bhabha Road, Colaba, Mumbai 400005, India e-mail: singh@tifr.res.in, vrana@tifr.res.in
² Joint Astronomy Programme, Department of Physics, Indian Institute of Science, Bangalore 560012, India

Corresponding author: V. R. Rana, vrana@tifr.res.in

Received: 19 February 2003
Accepted: 25 July 2003

Abstract

We present evidence for a spin period of 4070 s in a magnetic cataclysmic variable V1432 Aql, classified as a polar. The evidence is based on the analysis of archival X-ray data obtained from a 25 ks long and uninterrupted observations with XMM–Newton. We also detect modulation of the X-ray flux with the orbital period, various harmonics of the spin period, and side-bands due to beating of the spin period with the orbital period. The energy-dependent light curves and hardness ratios show a very complex behaviour with both the spin phase and the orbital phase, indicating the presence of multiple absorbers of different densities. The observed characteristics suggest the presence of a disk in the system and accretion via a disk-overflow mechanism as is commonly observed in intermediate polars.