Abstract Details

Name: APURBA BERA
Affiliation: NCRA-TIFR, Pune
Conference ID: ASI2019_365
Title : Atomic hydrogen and star formation in galaxies at intermediate redshifts
Authors and Co-Authors : Apurba Bera, Jayaram N. Chengalur, Nissim Kanekar & Jasjeet S. Bagla
Abstract Type : Oral
Abstract Category : Extragalactic Astronomy
Abstract : Understanding the evolution of galaxies over cosmic time is one of the most important goals of modern astrophysics. In the recent past a number of deep optical studies of high redshift galaxies have provided information on the evolution of the stellar mass, star formation rate, luminosity function and morphological properties of the galaxy population. However, these studies provide no information about the evolution of the neutral atomic hydrogen (HI) content of galaxies. Since atomic hydrogen provides the primary reservoir of the material required for star formation, understanding its evolution is fundamental for understanding galaxy evolution. The atomic hydrogen content of galaxies is best probed by their HI-21cm emission. The upgraded Giant Metrewave Radio Telescope (uGMRT) with its L-band (1.0-1.4 GHz) receivers is an excellent instrument to measure the HI-21cm emission from galaxies out to redshift of z < 0.4. Deep radio observation can also be used to estimate the star formation rates of high redshift galaxies from their radio continuum emission using the well established radio-FIR correlation, which gives a dust free estimate of the total star formation rate, unlike the optical/UV continuum or spectral lines which are subject to dust extinction. Comparing the radio derived star formation rates to that estimated from optical/UV indicators , it is possible to study the dust extinction suffered by different indicators as functions of redshift and different physical parameters of the galaxies. We are carrying out a deep uGMRT survey of the Extended Groth Strip with the L-band receivers to measure the HI content in the star forming galaxies at redshifts of z < 0.4 in the field. In this talk I will present the preliminary results on HI mass measurements and radio-derived star formation rates, from this study.