Time-resolved spectroscopy of AL Comae

被引：12

作者：

Howell, SB ^{[1
]}

Hauschildt, P

Dhillon, VS

机构：

[1] Univ Wyoming, Dept Phys & Astron, Laramie, WY 82071 USA

[2] Univ Georgia, Dept Phys & Astron, Athens, GA 30602 USA

[3] Univ Georgia, Ctr Simulat Phys, Athens, GA 30602 USA

[4] Royal Greenwich Observ, Cambridge CB3 0EZ, England

来源：

ASTROPHYSICAL JOURNAL | 1998年 / 494卷 / 02期

基金：

美国国家航空航天局; 美国国家科学基金会;

关键词：

stars; individual (AL Comae); low-mass; brown dwarfs; variables; other;

D O I：

10.1086/311187

中图分类号：

P1 [天文学];

学科分类号：

0704 ;

摘要：

We present time-resolved spectroscopy for AL Com, one of the faintest known tremendous outburst amplitude dwarf novae (TOADs). Using newly produced models for a white dwarf and red secondary, we show that the star AL Com has orbitally phase-resolved broad absorption features of yet unidentified origin and an optically thin accretion disk. Radial velocities measured from the few spectra available show essentially no motion of the white dwarf, leading to a strict upper limit on the secondary mass of less than or equal to 0.18 M., with a likely value of 0.04-0.09 M.. This agrees well with recent theoretical arguments placing the TOADs as post-period minimum cataclysmic variables.

引用

页码：L223 / L226

页数：4

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