The structure of the Galactic bar

被引:136
作者
Babusiaux, C
Gilmore, G
机构
[1] Univ Cambridge, Inst Astron, Cambridge CB3 0HA, England
[2] Free Univ Brussels, Inst Astron & Astrophys, B-1050 Brussels, Belgium
关键词
dust; extinction; Galaxy : bulge; Galaxy : stellar content; Galaxy : structure; infrared : stars;
D O I
10.1111/j.1365-2966.2005.08828.x
中图分类号
P1 [天文学];
学科分类号
0704 ;
摘要
We present a deep near-infrared wide-angle photometric analysis of the structure of the inner Galactic bar and central disc. The presence of a triaxial structure at the centre of the Galaxy is confirmed, consistent with a bar inclined at 22 degrees +/- 5.degrees 5 from the Sun - Galactic Centre line, extending to approximately 2.5 kpc from the Galactic Centre and with a rather small axis ratio. A feature at l = - 9.degrees 8 not aligned with this triaxiality suggests the existence of a second structure in the inner Galaxy, a double triaxiality or an inner ring. We argue that this is likely to be the signature of the end of the Galactic bar, at approximately 2.5 - 3 kpc, which is circumscribed by an inner pseudo-ring. No thick dust lane preceding the bar is detected and a hole in the dust distribution of the disc inside the bar radius is inferred.
引用
收藏
页码:1309 / 1319
页数:11
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