Designation: SRF Thesis Topic: Multi-wavelength study of Hot stellar population in Galactic Globular Clusters Thesis Supervisor: Dr. Ramakant S. Yadav gaurav 755 Cabin No. 2, Room No 14, New Building Personal webpage (Maintained by individual)
Ph.D. in Astronomy & Astrophysics during 2015 - present (under the supervision of Dr. Ramakant at Aries, Nainital , and Registered at University of Delhi under Prof. Patrick Das Gupta)
Research Interest and Description
Being one of the oldest stellar systems, Globular clusters (GCs) offer an excellent opportunity to test the theories of stellar evolution. GCs host mainly cooler giant population which are bright in Optical-Infrared. However, it also hosts a significant number of hot stellar population like horizontal branch (HB) stars, Extended horizontal branch (EHB), and Blue straggler stars (BSSs), etc. Because of the ongoing nuclear fusion in their core, these hot stellar population are bright in Ultraviolet (UV) wavelength, while the cooler giants are suppressed. Since, the earth absorbs the UV part of the spectrum, therefore, space-telescopes are quite useful. With the availability of the UVIT/ASTROSAT and Swift/UVOT data sets it is now possible to understand the UV properties of the hot stellar population.
Apart from the UV properties, BSSs are found to be a crucial probe to understand the dynamical evolution of the cluster. To fully exploit this opportunity, cluster members must be discerned from field stars, which can be achieved e.g. by a proper motion (PM) study. This allow the identification of cluster members occupying unusual locations in the H-R diagram. However, their sample estimation has always been a challenging task. In this regards, our aim is to investigate these objects using the wide-field astrometric data from HST in the central and GAIA DR2 in the external regions.