Stellar density distribution in the NIR on the Galactic plane at longitudes 15-27 deg. Clues for the Galactic bar?

Picaud, S.; Cabrera-Lavers, A.; Garzón, F.
Bibliographical reference

Astronomy and Astrophysics, v.408, p.141-151 (2003)

Advertised on:
9
2003
Number of authors
3
IAC number of authors
2
Citations
27
Refereed citations
21
Description
Garzón et al. (cite{Garzon97}), López-Corredoira et al. (cite{Lopez99}) and Hammersley et al. (cite{Hammersley00}) have identified in TMGS and DENIS data a large excess of stars at l=27deg and b=0o which might correspond to an in-plane bar. We compared near infrared CAIN star counts and simulations from the Besançon Model of Galaxy on 15 fields between 15o and 45o in longitude and -2o and 2o in latitude. Comparisons confirm the existence of an overdensity at longitudes lower than 27o 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.
Type