Are there really intergalactic hydrogen clouds in the Sculptor group
Description
High-sensitivity 21 cm observations of the region of the Sculptor group of galaxies reveal at least 30 H I clouds distributed over only the southern sector of the group. These new data add two striking complications to the picture of the clouds as H I companions of Sculptor galaxies: first, a much wider spatial distribution of clouds in marked contrast with the clustering of clouds around NGC 55 and NGC 300 previously reported by Mathewson, Cleary, and Murray; and second, a cloud velocity distribution which does not match that of the galaxies.We cannot reconcile the spatial and velocity distributions of the H I clouds with those of the group or of any subgroup. We conclude that there are no intergalactic H I clouds of > or =108 M/sub sun/ and galactic dimensions within the Sculptor group. Of a number of explanations alternative to group membership, we favor the identification of the clouds as a component of the Magellanic Stream which is seen in projection. Observations reported here of other nearby groups, combined with those of Sculptor, rule out the existence of a significant population of discrete H I clouds having the above properties
Additional details
Publishing Information
- Journal Title
- Astrophys. J.
- Journal Volume
- 227
- Journal Issue
- 3
- Series
- Astrophys. J.
- Journal Page Range
- 767-775
- ISSN
- 0004-637X
INIS
- Country of Publication
- United States
- Country of Input or Organization
- United States
- INIS RN
- 10471834
- Subject category
- S79: ASTROPHYSICS, COSMOLOGY AND ASTRONOMY;
- Descriptors DEI
- COSMIC RADIO SOURCES; ENERGY SPECTRA; GALAXY CLUSTERS; H1 REGIONS; INTERGALACTIC SPACE; RADIOWAVE RADIATION; SPATIAL DISTRIBUTION
- Descriptors DEC
- DISTRIBUTION; ELECTROMAGNETIC RADIATION; RADIATIONS; SPACE; SPECTRA