Abstract Details

Name: Anshuman Borgohain
Affiliation: Tezpur University
Conference ID: ASI2020_438
Title : Extended UV Disk in Blue Compact Dwarfs
Authors and Co-Authors : Anshuman Borgohain, Kanak Saha, Rupjyoti Gogoi
Abstract Type : Poster
Abstract Category : Extragalactic Astronomy
Abstract : The discovery of spatially Extended Ultra Violet (XUV) disks in nearby spiral galaxies in the recent past has opened up a new window to the understanding of galaxy mass assembly over cosmic time. All searches for XUV emission were confined so far to nearby galaxies (upto z ~ 0.05 or so) due to limited resolution and depth in the Far Ultra Violet (FUV) band of GALEX. Here, we report the presence of XUV disk in a sample of Blue Compact Dwarfs (BCDs) upto redshift of ~0.24, which are a class of low metallicity, low mass galaxies present in the GOODS-South field. The detection was done with the help of deep and high resolution FUV imaging using the Ultra-Violet Imaging Telescope on-board AstroSat. For all the confirmed XUV detection, we see the FUV emission extending beyond the optical stellar disk. Confirmed XUV disk and shallower profiles of the young UV disk as compared to the optical/infrared profiles suggest recent mass assembly in the outskirts of BCDs. In other words, our observations provide evidences for an ongoing inside-out growth in these dwarf galaxies.