posted on 2024-07-13, 03:18authored byPhilip Lah, Jayaram N. Chengalur, Frank H. Briggs, Matthew Colless, Roberto De Propris, Michael B. Pracy, W. J. G. de Blok
We use observations from the Giant Metrewave Radio Telescope (GMRT) to measure the atomic hydrogen gas content of star-forming galaxies at z = 0.24 (i.e. a look-backtime of ~3 Gyr). To measure the HI 21 cm emission signal we stack the signal from 121 galaxies with known optical positions and redshifts. We find an average HI mass for the galaxies of (2.26 ± 0.90) x 10^9 M-sun. We translate this HI measurement into a cosmic density of neutral gas at z=0.24 of Ωgas = (0.91 ± 0.42) x 10^-3. This value is consistent with that estimated from damped Lyα systems around this redshift.
Dark galaxies and lost baryons: International Astronomical Union Symposium 244, Cardiff, Wales, 25-29 June 2007 / Jonathan I. Davies and Michael J. Disney (eds.)
Conference name
Dark galaxies and lost baryons: International Astronomical Union Symposium 244, Cardiff, Wales, 25-29 June 2007 / Jonathan I. Davies and Michael J. Disney eds.