Abstract Details
| Name: Vikrant Jadhav Affiliation: IISc, Bengaluru Conference ID: ASI2019_294 Title : What does ASTROSAT reveal about M67? Authors and Co-Authors : Vikrant Jadhav, Annapurni Subramaniam, N. Sindhu Abstract Type : Poster Abstract Category : Stars, ISM and Galaxy Abstract : M67 is an old open cluster featuring variety of stellar population. We observed M67 using UVIT (Ultra Violet Imaging Telescope) on ASTROSAT. Our Far-UV observations detect member stars which include 16 Blue Straggler Stars (BSSs) candidates, 3 white dwarfs, 13 SB1 (Single-lined spectroscopic binaries) and 4 SB2 (Double-lined spectroscopic binaries including 2 triple systems). We constructed the Spectral Energy Distribution (SED) using UVIT, KPNO, 2MASS and WISE photometry to characterize the stars detected in UVIT. Star which show large UV excess are identified to have possible hot companions. Two component SED fits were performed and the best fitting SEDs are used to estimate Surface temperatures and radii of stars as well as those of the companion WDs. We identify and characterize many optically sub-luminous hot companions to a few BSSs and main-sequence stars, which are mostly classifies as SB1 systems. UVIT has thus helped to detect a large number of WD companions for many BSS and MS stars. We discuss the implication of this result for the formation pathways of BSSs. |