A long serendipitous XMM–Newton observation of the intermediate polar XY Ari1
Makaleler > Tam Makale · 2018
Yazarlar: Dicle ZENGİN ÇAMURDAN, S. Balman, V. BURWITZ
Monthly Notices of the Royal Astronomical Society, SCI Expanded İndekslerine Giren Dergi, Uluslararası, Wos, 2018, cilt 477, ss 4035-4045
DOI: 10.1093/mnras/sty906
Özet
XY Ari is one of the few known eclipsing intermediate polars. We present results from a detailed analysis of an unpublished archival observation using XMM–Newton EPIC pn and MOS data in a quiescent state of XY Ari. The X-ray orbital modulation and spin-pulse variations were investigated for energy-dependent modulations in different energy bands. The broad orbital modulation observed with various observations was confirmed with XMM–Newton in the hard X-ray (>1.6 keV). The EPIC light curves folded at the spin phases show a double-peak profile, as expected from two-pole accretion. The pulse profile is found to be energy-dependent. Hardness-ratio variations and energy modulation depth during spin modulation can be explained by photoelectric absorption. The simultaneously fitted EPIC spectra with a multi-temperature plasma emission model (CEVMKL) model yield a maximum plasma temperature of |$28^{+3.1}_{-2.9}$| keV with an iron abundance |$\mathrm{Fe}/\mathrm{Fe}_{\odot }=0.37^{+0.06}_{-0.05}$|. We find two intrinsic partial covering absorption columns of |$6.2^{+1.0}_{-0.9} \times 10^{22}$| and |$105.3^{+35.4}_{-30.4} \times 10^{22} \, \mathrm{cm^{-2}}$| with covering fractions of |$0.53^{+0.05}_{-0.04}$|, |$0.41^{+0.14}_{-0.13}$|, respectively. In addition, a Gaussian emission line at |$6.43^{+0.01}_{-0.02}$| keV with an equivalent width of |$51^{+12}_{-10}$| eV is required to account for fluorescent emission from neutral iron. The X-ray luminosity of the source is 4.2 × 1032 erg s−1 in the 0.2–10.0 keV energy band.