Neutral atomic hydrogen (H i) gas evolution in field galaxies at z similar to 0.1 and similar to 0.2

J. Rhee*, Martin A. Zwaan, Frank H. Briggs, Jayaram N. Chengalur, Philip Lah, Tom Oosterloo, Thijs van der Hulst

*Bijbehorende auteur voor dit werk

OnderzoeksoutputAcademicpeer review

67 Citaten (Scopus)
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Samenvatting

We measure the neutral atomic hydrogen (H i) gas content of field galaxies at intermediate redshifts of z similar to 0.1 and similar to 0.2 using hydrogen 21-cm emission lines observed with the Westerbork Synthesis Radio Telescope. In order to make high signal-to-noise ratio detections, an H i signal stacking technique is applied: H i emission spectra from multiple galaxies, optically selected by the second Canadian Network for Observational Cosmology redshift survey project, are co-added to measure the average H i mass of galaxies in the two redshift bins. We calculate the cosmic H i gas densities ((Hi)) at the two redshift regimes and compare those with measurements at other redshifts to investigate the global evolution of the H i gas density over cosmic time. From a total of 59 galaxies at z similar to 0.1 we find (Hi) = (0.33 +/- 0.05) x 10(-3), and at z similar to 0.2 we find (Hi) = (0.34 +/- 0.09) x 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 (Hi) at z similar to 0.1 and similar to 0.2 are consistent with the H i gas density at z similar to 0 and that all measurements of (Hi) from 21-cm emission observations at z less than or similar to 0.2 are in agreement with no evolution of the H i gas content in galaxies during the last 2.4 Gyr.

Originele taal-2English
Pagina's (van-tot)2693-2706
Aantal pagina's14
TijdschriftMonthly Notices of the Royal Astronomical Society
Volume435
Nummer van het tijdschrift3
DOI's
StatusPublished - 1-nov-2013

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