Stellar density distribution in the NIR on the Galactic plane at longitudes 15-7 deg.: Clues for the Galactic bar?

被引:25
作者
Picaud, S
Cabrera-Lavers, A
Garzón, F
机构
[1] Observ Besancon, CNRS, UMR 6091, F-25010 Besancon, France
[2] Inst Astrofis Canarias, Tenerife 38200, Spain
[3] Univ La Laguna, Dept Astrofis, Tenerife, Spain
关键词
Galaxy : structure; Galaxy : stellar content; Galaxy : disk;
D O I
10.1051/0004-6361:20030935
中图分类号
P1 [天文学];
学科分类号
0704 ;
摘要
Garzon et al. (1997), Lopez-Corredoira et al. (1999) and Hammersley et al. (2000) have identified in TMGS and DENIS data a large excess of stars at l = 27degrees and b = 0degrees which might correspond to an in-plane bar. We compared near infrared CAIN star counts and simulations from the Besancon Model of Galaxy on 15 fields between 15degrees and 45degrees in longitude and -2degrees and 2degrees in latitude. Comparisons confirm the existence of an overdensity at longitudes lower than 27degrees which is inhomogeneous and decreases very steeply off the Galactic plane. The observed excess in the star distribution over the predicted density is even higher than 100%. Its distance from the sun is estimated to be lower than 6 kpc. If this overdensity corresponds to the stellar population of the bar, we estimate its half-length to 3.9 +/- 0.4 kpc and its angle from the Sun-center direction to 45 +/- 9 degrees.
引用
收藏
页码:141 / 151
页数:11
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