Discovery of a variable star population in NGC 2808

被引:18
作者
Corwin, TM
Catelan, M
Borissova, J
Smith, HA
机构
[1] Pontificia Univ Catolica Chile, Dept Astron & Astrofis, Santiago 7820436, Chile
[2] Michigan State Univ, Dept Phys & Astron, E Lansing, MI 48824 USA
[3] Univ N Carolina, Dept Phys, Charlotte, NC 28223 USA
基金
美国国家科学基金会;
关键词
galaxy : globular clusters : individual : NGC 2808; stars : horizontal-branch; stars : variables : RR Lyr;
D O I
10.1051/0004-6361:20035944
中图分类号
P1 [天文学];
学科分类号
0704 ;
摘要
We have applied the image subtraction method to images of the peculiar, bimodal-horizontal branch globular cluster NGC 2808, taken over a total of six nights over a range of five months. As a result, we have found, for the first time, a sizeable population of variable stars in the crowded inner regions of the cluster, thus raising the known RR Lyrae population in the cluster to a total of 78 stars. In addition, an eclipsing binary and two other variables with periods longer than 1 day were also found. Periods, positions and (differential) light curves are provided for all the detected variables. The Oosterhoff classification of NGC 2808, which has recently been associated with a previously unknown dwarf galaxy in Canis Major, is briefly discussed.
引用
收藏
页码:667 / 672
页数:6
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