| Abstract : | Disk warps are common features in spiral Galaxies. It has been observed that around 50-70% of the edge-on disk galaxies exhibit warped structures. The warp is supposed to be formed by continuous gravitational torque and perturbations on the disk of the galaxy from various sources. The study of galactic warps could reveal key information on the formation history of galaxies. Our location within the Galactic disc makes it hard to trace the entire structure of the Milky Way. However, the advantage of this orientation is that we can study the stars in greater detail as compared to any external galaxies. Thus, Our Milky Way presents a unique case study for understanding the structure and evolution history of the galaxies. Many observations (HI, dust, star-forming regions, stellar distributions) have suggested that the disk of our Galaxy is also warped, i.e. disk is not flat but curved upward in one direction and downwards in another. However, its origin is still a matter of debate. In order to understand the origin of the warp, we should map the structure with different age populations.
In our study, we use numerously present distance indicator: red clump stars, to trace the structure of the Milky Way disk. The red clump stars were extracted from 2MASS colour-magnitude (J-Ks, J) diagrams in the Galactic plane, avoiding the bulge region (40° <= l <= 340° & -10° <= b <= 10°). A total of 10 Million stars were selected as red clump candidates. The distribution of these red clump candidates in the R-Z plane shows disk warping upwards for l < 180° and downwards for l > 180°. My presentation would cover the details of sample preparation and results on warp structure.
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