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

S. Picaud·A. Cabrera-Lavers·F. Garzon
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Abstract

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=27 deg and b=0 deg 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 15 deg and 45 deg in longitude and -2 deg and 2 deg in latitude. Comparisons confirm the existence of an overdensity at longitudes lower than 27 deg 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.

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S. Picaud, A. Cabrera-Lavers, F. Garzon. 2003-06-30. Stellar density distribution in the NIR on the Galactic plane at longitudes 15-27 deg. Clues for the Galactic bar ?. https://doi.org/10.1051/0004-6361%3A20030935

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