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

¹ CNRS UMR 6091, Observatoire de Besançon, BP 1615, 25010 Besançon Cedex, France
² Instituto de Astrofísica de Canarias, 38200 La Laguna, Tenerife, Spain
³ Departamento de Astrofísica, Universidad de La Laguna, Tenerife, Spain

Corresponding author: S. Picaud, picaud@obs-besancon.fr

Received: 6 March 2003
Accepted: 28 May 2003

Abstract

Garzón et al. ([CITE]), López-Corredoira et al. ([CITE]) and Hammersley et al. ([CITE]) have identified in TMGS and DENIS data a large excess of stars at and 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 15° and 45° in longitude and and 2° in latitude. Comparisons confirm the existence of an overdensity at longitudes lower than 27° 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  kpc and its angle from the Sun-center direction to  degrees.