The Galactic rotation curve from red clump stars

Evidence for the Galactic Bar from the Two Color Photometryof the Bulge Red Clump Stars

Color-magnitude Diagram Distribution of the Bulge Red Clump Stars – Evidence for the Galactic Bar

The color-magnitude diagrams of ∼ 5 × 10 stars obtained for 13 fields towards the Galactic bulge with the OGLE project reveal a well-defined population of bulge red clump stars. We find that the distributions of the extinction-adjusted apparent magnitudes of the red clump stars in fields lying at l = ±5 in galactic longitude differ by 0.37± 0.025 mag. Assuming that the intrinsic luminosity dist...

Modelling the Galactic bar using OGLE-II Red Clump Giant Stars

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 se...

Modelling the Galactic Bar Using Red Clump Giants

The color-magnitude diagrams of ∼ 7×105 stars obtained for 12 fields across the Galactic bulge with the OGLE project reveal a well-defined population of bulge red clump giants. We find that the distributions of the apparent magnitudes of the red clump stars are systematically fainter when moving towards lower galactic l fields. The most plausible explanation of this distinct trend is that the G...

Constraining the Galactic Bar Parameters with Red Clump Giants

Red clump giants in the Galactic bulge occupy a distinct region in the colour magnitude diagram. They have a very small spread in intrinsic luminosities and their number counts have a well defined peak. We show that these characteristics can be used to constrain the differences in the streaming motions of stars on the near side and those on the far side. We propose two methods to select two sam...