Astronomy and Astrophysics – Astrophysics – Galaxy Astrophysics
Scientific paper
2009-03-05
Astronomy and Astrophysics
Astrophysics
Galaxy Astrophysics
A&A accepted
Scientific paper
AIMS:The aim of this paper is to study the characteristics of the stellar populations and the metallicity distribution in the Galactic bulge. We study the entire stellar population, but also retrieve information using only the red clump stars. METHODS: To study the characteristics of the stellar populations and the metallicity distribution in the Galactic bulge, we compared the output of the galaxy model TRILEGAL, which implements the Binney et al. (1997) bulge model, with observations from 2MASS and OGLE-II. A minimisation procedure has been set up to retrieve the best fitting model with different stellar populations and metallicity distributions. RESULTS: Using the TRILEGAL code we find that the best model resembling the characteristics of the Galactic bulge is a model with the distance to the Galactic centre $R_0 = 8.7\pm^{0.57}_{0.43}$ kpc, the major axis ratios of the bar $1:\eta:\zeta = 1 : 0.68\pm_{0.19}^{0.05} : 0.31\pm_{0.04}^{0.06}$, and the angle between the Sun-centre line and the bar $\phi = 15\deg\pm_{12.7}^{13.3}$. Using these parameters the best model is found for a burst of 8 Gyr, although it is almost indistinguishable from models with ages of 9 and 10 Gyr. The metallicity distribution found is consistent with metallicity distributions in the literature based on spectroscopic results.
Girardi Leo
Groenewegen Martin A. T.
Vanhollebeke Evelien
No associations
LandOfFree
Stellar populations in the Galactic bulge does not yet have a rating. At this time, there are no reviews or comments for this scientific paper.
If you have personal experience with Stellar populations in the Galactic bulge, we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and Stellar populations in the Galactic bulge will most certainly appreciate the feedback.
Profile ID: LFWR-SCP-O-115130