Multi-wavelength spectrophotometry of EX Hydrae

被引:26
作者
Eisenbart, S [1 ]
Beuermann, K [1 ]
Reinsch, K [1 ]
Gänsicke, BT [1 ]
机构
[1] Univ Sternwarte, D-37083 Gottingen, Germany
关键词
stars : individual : EX Hydrae; cataclysmic variables; accretion;
D O I
10.1051/0004-6361:20011655
中图分类号
P1 [天文学];
学科分类号
0704 ;
摘要
We present phase-resolved infrared and optical spectrophotometry of the intermediate polar EXHya supplemented by archival ultraviolet data. The spin-modulated emission from the accretion funnel and the emission from the accretion disk or ring contain substantial optically thin components. The white dwarf dominates the unmodulated flux in the ultraviolet and is identified by numerous absorption lines. Metal absorption in the accretion curtain may add to the observed spectral features. The secondary star is of spectral type M4 +/- 1 and is detected by its ellipsoidal modulation. We derive a distance of 65 +/- 11 pc which makes EX Hydrae one of the closest cataclysmic variables with a known distance. The luminosity derived from the integrated overall spectral energy distribution is 3 x 10(32) erg s(-1). The accretion rate of 3 x 10(15) g s(-1) (for an 0.6 M-. white dwarf) is in reasonable agreement with the rates expected from angular momentum loss by gravitational radiation and from the observed spin-up of the white dwarf.
引用
收藏
页码:984 / 998
页数:15
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