HIGHz: a survey of the most H I-massive galaxies at z ∼ 0.2
Abstract
We present the results of the HIGHz Arecibo survey, which measured the H I content of 39 galaxies at redshift z > 0.16 selected from the Sloan Digital Sky Survey. These are all actively star-forming, disc-dominated systems in relatively isolated environments, with stellar and H I masses larger than 1010 M⊙ and redshifts 0.17 ≤ z ≤ 0.25. Our sample includes not only the highest-redshift detections of H I emission from individual galaxies to date, but also some of the most H I-massive systems known. Despite being exceptionally large, the H I reservoirs of these galaxies are consistent with what is expected from their ultraviolet and optical properties. This, and the fact that the galaxies lie on the baryonic Tully-Fisher relation, suggests that HIGHz systems are rare, scaled-up versions of local disc galaxies. We show that the most H I-massive galaxies discovered in the Arecibo Legacy Fast ALFA survey are the local analogues of HIGHz, and discuss the possible connection between our sample and the turbulent, gas-rich discs identified at z ∼ 1. The HIGHz sample provides a first glimpse into the properties of the massive, H I-rich galaxies that will be detected at higher redshifts by the next generation H I surveys with the Square Kilometre Array and its pathfinders.
- Publication:
-
Monthly Notices of the Royal Astronomical Society
- Pub Date:
- February 2015
- DOI:
- 10.1093/mnras/stu2241
- arXiv:
- arXiv:1410.7464
- Bibcode:
- 2015MNRAS.446.3526C
- Keywords:
-
- galaxies: evolution;
- galaxies: fundamental parameters;
- galaxies: kinematics and dynamics;
- radio lines: galaxies;
- Astrophysics - Astrophysics of Galaxies
- E-Print:
- 20 pages, 11 figures, 3 tables. Accepted for publication in MNRAS. Version with high resolution figures available at http://astronomy.swin.edu.au/~bcatinel/publications.htm