H I extent and deficiency of spiral galaxies in the Virgo cluster
Abstract
Neutral hydrogen observations mapping along the optical major axis have been made with the Arecibo 305-m telescope and flat feed system for 24 spiral galaxies in the Virgo cluster. Comparison of observed flux integrals with those obtained from a numerical convolution of the antenna beam pattern and an assumed H I surface density distribution yields a measure of an effective H I size, taken to be that radius interior to which lies 70% of the total H I mass. The neutral hydrogen properties of the Virgo cluster spirals have been compared with those of a similar sample of isolated galaxies. We find that, for a given optical diameter, a Virgo core galaxy has a smaller H I extent than its optical counterpart; we measure the ratio of the H I to optical Holmberg diameter d/sub Htsi//d/sub Ho/ to be 0.70 for the 19 galaxies within a five degree projected radius of the cluster center, whereas those outside show d/sub Htsi//d/sub Ho/ approx. =1.10. Using the relation derived between the optical linear diameter and the H I mass, we are able to define a H I deficiency parameter and find that the galaxies in the Virgo core are, on the average,more »
- Authors:
- Publication Date:
- Research Org.:
- Arecibo Observatory, Arecibo, Puerto Rico 00613
- OSTI Identifier:
- 5984198
- Resource Type:
- Journal Article
- Journal Name:
- Astron. J.; (United States)
- Additional Journal Information:
- Journal Volume: 88:7
- Country of Publication:
- United States
- Language:
- English
- Subject:
- 71 CLASSICAL AND QUANTUM MECHANICS, GENERAL PHYSICS; GALAXIES; H1 REGIONS; GALAXY CLUSTERS; SPATIAL DISTRIBUTION; GHZ RANGE 01-100; SPIRAL CONFIGURATION; CONFIGURATION; COSMIC RADIO SOURCES; DISTRIBUTION; FREQUENCY RANGE; GHZ RANGE; 640103* - Astrophysics & Cosmology- Quasi-Stellar, Radio, & X-Ray Sources- (-1987); 640105 - Astrophysics & Cosmology- Galaxies
Citation Formats
Giovanelli, R, and Haynes, M P. H I extent and deficiency of spiral galaxies in the Virgo cluster. United States: N. p., 1983.
Web. doi:10.1086/113376.
Giovanelli, R, & Haynes, M P. H I extent and deficiency of spiral galaxies in the Virgo cluster. United States. https://doi.org/10.1086/113376
Giovanelli, R, and Haynes, M P. 1983.
"H I extent and deficiency of spiral galaxies in the Virgo cluster". United States. https://doi.org/10.1086/113376.
@article{osti_5984198,
title = {H I extent and deficiency of spiral galaxies in the Virgo cluster},
author = {Giovanelli, R and Haynes, M P},
abstractNote = {Neutral hydrogen observations mapping along the optical major axis have been made with the Arecibo 305-m telescope and flat feed system for 24 spiral galaxies in the Virgo cluster. Comparison of observed flux integrals with those obtained from a numerical convolution of the antenna beam pattern and an assumed H I surface density distribution yields a measure of an effective H I size, taken to be that radius interior to which lies 70% of the total H I mass. The neutral hydrogen properties of the Virgo cluster spirals have been compared with those of a similar sample of isolated galaxies. We find that, for a given optical diameter, a Virgo core galaxy has a smaller H I extent than its optical counterpart; we measure the ratio of the H I to optical Holmberg diameter d/sub Htsi//d/sub Ho/ to be 0.70 for the 19 galaxies within a five degree projected radius of the cluster center, whereas those outside show d/sub Htsi//d/sub Ho/ approx. =1.10. Using the relation derived between the optical linear diameter and the H I mass, we are able to define a H I deficiency parameter and find that the galaxies in the Virgo core are, on the average, H I deficient by a factor of 2.7 with respect to the isolated galaxies. The similarity of the relationship between the H I mass and the H I linear diameter, within the statistical errors, for both gas deficient and normal galaxies, implies that the linear extent of the H I distribution within a galaxy is well correlated with its total H I mass. The stripping mechanisms responsible for the H I deficiency observed in cluster galaxies, therefore, do not substantially alter the average H I surface density, but rather lower the H I mass and size to values expected for an optically smaller galaxy. The dependence of the H I deficiency on the velocity of a galaxy with respect to the cluster suggests that the mechanism responsible for the removal of the interstellar gas from the galaxy is the ram pressure sweeping of the intracluster gas.},
doi = {10.1086/113376},
url = {https://www.osti.gov/biblio/5984198},
journal = {Astron. J.; (United States)},
number = ,
volume = 88:7,
place = {United States},
year = {Fri Jul 01 00:00:00 EDT 1983},
month = {Fri Jul 01 00:00:00 EDT 1983}
}