We present the orbital phase‐resolved spectra of an intermediate polar, EX Hya, together with the spin phase‐resolved spectra during two different epochs using the X‐ray Multi‐Mirror Mission (XMM–Newton), European Photon Imaging Camera (pn instrument). We find that the source at the two epochs has the same X‐ray luminosity of ∼6.5 × 1031 erg s−1. We detect spectral variations between the 2000 and 2003 observations of the source. We fitted the spectrum using a neutral hydrogen absorption model with or without covering fraction together with Gaussians for emission lines, two collisional equilibrium plasma emission models (MEKAL) and a cooling‐flow plasma emission model (VMCFLOW). We find that two of the three emission components (kT= 0.6–0.8 and 1.3–1.7 keV) fitted by the MEKAL models are almost constant over the spin and orbital phases and also over the two different epochs with the normalization varying directly proportional to the flux when the data are folded according to the orbital and spin phase indicating that the slight variation may be due to occultation. The emission modelled by the VMCFLOW changes over the spin and orbital phases and the 2000 and 2003 observations reveal two different ranges of temperatures (3–33 and 8–61 keV, respectively) that model the shock zone in the accretion column(s). The ratios of the spin maximum to minimum and the orbital maximum to minimum spectra along with the increase in the plasma temperatures indicate that the spectrum gets harder in the minimum phases of both orbital and spin periods. In the 2003 observation, a 6.4 keV fluorescent Fe emission line is present at the orbital minima in a range of phases from 0.9 to 1.3 and it is absent otherwise. This indicates that there is reflection from the disc most likely from a large bulge at the accretion impact zone.

We present the Chandra ACIS‐S3 data of the old classical nova RR Pic (1925). The source has a count rate of 0.067 ± 0.002 count s−1 in the 0.3–5.0 keV energy range. We detect the orbital period of the underlying binary system in the X‐ray wavelengths. We also find that the neutral hydrogen column density differs for orbital minimum and orbital maximum spectra with values 0.25+0.23−0.18× 1022 and 0.64+0.13−0.14× 1022 cm−2 at 3σ confidence level. The X‐ray spectrum of RR Pic can be represented by a composite model of bremsstrahlung with a photoelectric absorption, two absorption lines centered around 1.1–1.4 keV and five Gaussian lines centered at emission lines around 0.3–1.1 keV corresponding to various transitions of S, N, O, C, Ne and Fe. The bremsstrahlung temperature derived from the fits ranges from 0.99 to 1.60 keV and the unabsorbed X‐ray flux is found to be 2.5+0.4−1.2× 10−13 erg  cm−2 s−1 in the 0.3–5.0 keV range with a luminosity of 1.1 ± 0.2 1031 erg s−1 at 600 pc. We also detect excess emission in the spectrum possibly originating from the reverse shock in the ejecta. A fit with a cooling flow plasma emission model shows enhanced abundances of He, C, N, O and Ne in the X‐ray emitting region indicating existence of diffusive mixing.

We present the orbital-phase resolved analysis of an archival FO Aqr observation obtained using the X-ray Multi-Mirror Mission (XMM-Newton), European Photon Imaging Camera (pn instrument). We investigate the variation of the spin pulse amplitudes over the orbital period in order to account for the effects of orbital motion on spin modulation. The semi-amplitude variations are in phase with the orbital modulation, changing from (38.0±1.8)% at the orbital maximum to (13.3±3.7)% at the orbital minimum. The spectral parameters also show changes over the orbital period. One of the absorption components increase by a factor of 5 between the orbital minimum and maximum. We interpret that this absorption arises from the bulge where accretion stream from the secondary impacts the disk. The spectrum extracted from the orbital minima and maxima can be fitted with a warm absorber model yielding values N H = 2.09 +0.98 −1.09 × 10 22 and 0.56 +0.26 −0.15 × 10 22 cm −2 ; and log(ξ) = 0.23 +0.37 −0.26 and <0.30 erg cm s −1 respectively, indicating the existence of ionized absorption from the bulge at the impact zone which is spread out on the disk. The absorption due to accretion curtain and/or column which causes the spin modulation can be distinguished from the disk absorption via spectral modeling.

Abstract. Intermediate Polars (IPs): EX Hya and FO Aqr whichs are a subclass of Cataclysmic Variables (CVs) where a white dwarf with magnetic field strength of about 1-10 MG accretes material from a main sequence companion through a truncated disc. In this talk we present orbital and spin phase-resolved X-ray spectroscopy of EX Hya and orbital phase-resolved X-ray spectroscopy of FO Aqr. We utilize XMM-Newton archive data of these objects for analysis. We investigate the change of the source spectrum over the spin and orbital periods. This analysis enhances our understanding about the accretion structure in these systems, temperature and composition of the X-ray emitting region together with the structure of the outer accretion disc and absorption in the system

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