Modelling the Galactic bar using OGLE-II Red Clump Giant Stars
نویسندگان
چکیده
Red clump giant stars can be used as distance indicators to trace the mass distribution of the Galactic bar. We use RCG stars from 44 bulge fields from the OGLE-II microlensing collaboration database to constrain analytic tri-axial models for the Galactic bar. We find the bar major axis is oriented at an angle of 24◦ – 27◦ to the Sun-Galactic centre line-of-sight. The ratio of semi-major and semi-minor bar axis scale lengths in the Galactic plane x0, y0, and vertical bar scale length z0, is x0 : y0 : z0 = 10 : 3.5 : 2.6, suggesting a slightly more prolate bar structure than the working model of Gerhard (2002) which gives the scale length ratios as x0 : y0 : z0 = 10 : 4 : 3.
منابع مشابه
Modelling the Galactic Bar Using Red Clump Giants
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