Minchin, R. F., Auld, R., Davies, Jonathan Ivor, Karachentsev, I. D., Keenan, O. C., Momjian, E., Rodriguez, R., Taber, T. and Taylor, R. 2016. The Arecibo Galaxy Environment Survey IX: the isolated galaxy sample. Monthly Notices of the Royal Astronomical Society 455 (4) , pp. 3430-3435. 10.1093/mnras/stv2557 |
Abstract
We have used the Arecibo L-band Feed Array (ALFA) to map three regions, each of 5 deg2, around the isolated galaxies NGC 1156, UGC 2082, and NGC 5523. In the vicinity of these galaxies we have detected two dwarf companions: one near UGC 2082, previously discovered by the Arecibo Legacy Fast ALFA (ALFALFA) survey, and one near NGC 1156, discovered by this project and reported in an earlier paper. This is significantly fewer than the 15.4+1.7−1.5 that would be expected from the field H i mass function from ALFALFA or the 8.9 ± 1.2 expected if the H i mass function from the Local Group applied in these regions. The number of dwarf companions detected is, however, consistent with a flat or declining H i mass function as seen by a previous, shallower, H i search for companions to isolated galaxies. We attribute this difference in H i mass functions to the different environments in which they are measured. This agrees with the general observation that lower ratios of dwarf to giant galaxies are found in lower density environments.
Item Type: | Article |
---|---|
Date Type: | Publication |
Status: | Published |
Schools: | Physics and Astronomy |
Subjects: | Q Science > QB Astronomy Q Science > QC Physics |
Uncontrolled Keywords: | galaxies: individual: NGC 1156; galaxies: individual: NGC 5523; galaxies: individual: UGC 2082; galaxies: luminosity function, mass function; radio lines: galaxies |
Publisher: | Oxford University Press |
ISSN: | 0035-8711 |
Date of Acceptance: | 29 October 2015 |
Last Modified: | 04 Jun 2017 09:10 |
URI: | https://orca.cardiff.ac.uk/id/eprint/91422 |
Citation Data
Cited 3 times in Scopus. View in Scopus. Powered By Scopus® Data
Actions (repository staff only)
Edit Item |