The multi-temperature X-ray spectrum of the intermediate polar V1223 Sagittarii

被引:25
作者
Beardmore, AP [1 ]
Osborne, JP
Hellier, C
机构
[1] Keele Univ, Dept Phys, Keele ST5 5BG, Staffs, England
[2] Univ Leicester, Dept Phys & Astron, Leicester LE1 7RH, Leics, England
关键词
accretion; accretion discs; binaries : close; stars : individual : V1223 Sgr; novae; cataclysmic variables; X-rays : stars;
D O I
10.1046/j.1365-8711.2000.03477.x
中图分类号
P1 [天文学];
学科分类号
0704 ;
摘要
We describe fits to the Ginga LAC and ASCA GIS and SIS X-ray spectra of the intermediate polar V1223 Sgr using a multi-temperature emission model and including reflection from the white dwarf surface. Shock temperatures of T-S = 30(-4)(+12), 54(-15)(+26) and 47(-12)(+30)keV were obtained for the Ginga LAC, ASCA GIS and SIS instruments, respectively, giving a mean value of 47(-12)(+13)keV. The data reveal significant amounts of reflection as well as a heavy metal underabundance by a factor of similar to 2. Multiple absorption components are required to successfully model the observed X-ray spectra at low energies, suggesting the presence of complex intrinsic absorption. All data sets reveal a low-energy spectral hardening at the minimum in the spin cycle caused by an increase in the amount of absorption at this phase. The requirement of such complex absorption is becoming increasingly common in the good quality X-ray spectra from magnetic cataclysmic variables.
引用
收藏
页码:307 / 315
页数:9
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