Please use this identifier to cite or link to this item: http://hdl.handle.net/1959.3/229515

Title

Deep 21cm H I observations at z ~ 0.1: the precursor to the Arecibo ultra deep survey

Author(s)

Freudling, Wolfram;  Staveley-Smith, Lister;  Catinella, Barbara;  Minchin, Robert;  Calabretta, Mark;  Momjian, Emmanuel;  Zwaan, Martin;  Meyer, Martin;  O'Neil, Karen

Abstract

The 'ALFA Ultra Deep Survey' (AUDS) is an ongoing 21-cm spectral survey with the Arecibo 305m telescope. AUDS will be the most sensitive blind survey undertaken with Arecibo's 300 MHz Mock spectrometer. The survey searches for 21-cm HI line emission at redshifts between 0 and 0.16. The main goals of the survey are to investigate the HI content and probe the evolution of HI gas within that redshift region. In this paper, we report on a set of precursor observations with a total integration time of 53 hours. The survey detected a total of eighteen 21-cm emission lines at redshifts between 0.07 and 0.15 in a region centered around ra~0:00h, dec= 15:42deg. The rate of detection is consistent with the one expected from the local HI mass function. The derived relative HI density at the median redshift of the survey is rho_HI[z=0.125]=(1.0+/-0.3)*rho_0, where rho_0 is the HI density at zero redshift.

Publication type

Journal article

Source

Astrophysical Journal Letters, Vol. 727, no. 1 (Jan 2011), article no. 40

Publication year

2011

FOR Code(s)

0201 Astronomical and Space Sciences

Keyword(s)

Cosmology observations;  Galaxy evolution;  Radio lines

Publisher

Institute of Physics Publishing

ISSN

2041-8205

Publisher URL

http://dx.doi.org/10.1088/0004-637x/727/1/40

Copyright

Copyright © 2011 The American Astronomical Society. All rights reserved. The American Astronomical Society does not allow Swinburne Research Bank to archive either the accepted manuscript or the published version of the article. However you can find an earlier version of the full text here: http://arxiv.org/abs/1011.0877

Peer reviewed