A new population of extended, luminous star clusters in the halo of M31

被引:124
作者
Huxor, AP [1 ]
Tanvir, NR
Irwin, MJ
Ibata, R
Collett, JL
Ferguson, AMN
Bridges, T
Lewis, GF
机构
[1] Univ Hertfordshire, Ctr Astrophys Res, Hatfield AL10 9AB, Herts, England
[2] Astron Inst, Cambridge CB3 0HA, England
[3] Observ Strasbourg, F-67000 Strasbourg, France
[4] Univ Edinburgh, Royal Observ, Astron Inst, Edinburgh EH9 3HJ, Midlothian, Scotland
[5] Queens Univ, Dept Phys, Kingston, ON K7M 3N6, Canada
[6] Univ Sydney, Astron Inst, Sch Phys, Sydney, NSW 2006, Australia
关键词
galaxies : individual : M31; galaxies : star clusters : galaxies;
D O I
10.1111/j.1365-2966.2005.09086.x
中图分类号
P1 [天文学];
学科分类号
0704 ;
摘要
We present three new clusters discovered in the halo of M31 which, although having globular-like colours and luminosities, have unusually large half-light radii, similar to 30 pc. They lie at projected galactocentric distances of approximate to 15 to approximate to 35 kpc. These objects begin to fill the gap in parameter space between globular clusters and dwarf spheroidals, and are unlike any clusters found in the Milky Way, or elsewhere to date. Colour-magnitude diagrams, integrated photometric properties and derived King profile fit parameters are given, and we discuss possible origins of these clusters and their relationships to other populations.
引用
收藏
页码:1007 / 1012
页数:6
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