%0 Generic %1 rhee2013neutral %A Rhee, Jonghwan %A Zwaan, Martin A. %A Briggs, Frank H. %A Chengalur, Jayaram N. %A Lah, Philip %A Oosterloo, Tom %A van der Hulst, Thijs %D 2013 %K HI dla emission evolution gas redshift %T Neutral atomic hydrogen (HI) gas evolution in field galaxies at z ~ 0.1 and 0.2 %U http://arxiv.org/abs/1308.1462 %X We measure the neutral atomic hydrogen (HI) gas content of field galaxies at intermediate redshifts of z ~ 0.1 and z ~ 0.2 using hydrogen 21-cm emission lines observed with the Westerbork Synthesis Radio Telescope (WSRT). In order to make high signal-to-noise ratio detections, an HI signal stacking technique is applied: HI emission spectra from multiple galaxies, optically selected by the CNOC2 redshift survey project, are co-added to measure the average HI mass of galaxies in the two redshift bins. We calculate the cosmic HI gas densities (Ømega_HI) at the two redshift regimes and compare those with measurements at other redshifts to investigate the global evolution of the HI gas density over cosmic time. From a total of 59 galaxies at z ~ 0.1 we find Ømega_HI = (0.33 $\pm$ 0.05) ~ $\times$ 10$^-3$, and at z ~ 0.2 we find Ømega_HI = (0.34 $\pm$ 0.09) ~ $\times$ 10$^-3$, based on 96 galaxies. These measurements help bridge the gap between high-z damped Lyman-$\alpha$ observations and blind 21-cm surveys at $z=$ 0. We find that our measurements of Ømega_HI at z ~ 0.1 and 0.2 are consistent with the HI gas density at z ~ 0 and that all measurements of Ømega_HI from 21-cm emission observations at $z ła$ ~ 0.2 are in agreement with no evolution of the HI gas content in galaxies during the last 2.4 Gyr.

@misc{rhee2013neutral, abstract = {We measure the neutral atomic hydrogen (HI) gas content of field galaxies at intermediate redshifts of z ~ 0.1 and z ~ 0.2 using hydrogen 21-cm emission lines observed with the Westerbork Synthesis Radio Telescope (WSRT). In order to make high signal-to-noise ratio detections, an HI signal stacking technique is applied: HI emission spectra from multiple galaxies, optically selected by the CNOC2 redshift survey project, are co-added to measure the average HI mass of galaxies in the two redshift bins. We calculate the cosmic HI gas densities ({\Omega}_{HI}) at the two redshift regimes and compare those with measurements at other redshifts to investigate the global evolution of the HI gas density over cosmic time. From a total of 59 galaxies at z ~ 0.1 we find {\Omega}_{HI} = (0.33 $\pm$ 0.05) ~ $\times$ 10$^{-3}$, and at z ~ 0.2 we find {\Omega}_{HI} = (0.34 $\pm$ 0.09) ~ $\times$ 10$^{-3}$, based on 96 galaxies. These measurements help bridge the gap between high-z damped Lyman-$\alpha$ observations and blind 21-cm surveys at $z=$ 0. We find that our measurements of {\Omega}_{HI} at z ~ 0.1 and 0.2 are consistent with the HI gas density at z ~ 0 and that all measurements of {\Omega}_{HI} from 21-cm emission observations at $z \la$ ~ 0.2 are in agreement with no evolution of the HI gas content in galaxies during the last 2.4 Gyr.}, added-at = {2013-08-08T16:50:42.000+0200}, author = {Rhee, Jonghwan and Zwaan, Martin A. and Briggs, Frank H. and Chengalur, Jayaram N. and Lah, Philip and Oosterloo, Tom and van der Hulst, Thijs}, biburl = {https://www.bibsonomy.org/bibtex/2b2904b8b6629ec12a366ea55d4e3412a/miki}, description = {[1308.1462] Neutral atomic hydrogen (HI) gas evolution in field galaxies at z ~ 0.1 and 0.2}, interhash = {dfbd84c3f25fb84a4ba56bc975721076}, intrahash = {b2904b8b6629ec12a366ea55d4e3412a}, keywords = {HI dla emission evolution gas redshift}, note = {cite arxiv:1308.1462Comment: 14 pages, 9 figures, accepted by MNRAS}, timestamp = {2013-08-08T16:50:42.000+0200}, title = {Neutral atomic hydrogen (HI) gas evolution in field galaxies at z ~ 0.1 and 0.2}, url = {http://arxiv.org/abs/1308.1462}, year = 2013 }