| | |
| | |
Stat |
Members: 3645 Articles: 2'504'928 Articles rated: 2609
25 April 2024 |
|
| | | |
|
Article overview
| |
|
An HI line search for optically identified dwarf galaxy candidates in the M81 group | W. van Driel
; R.C. Kraan-Korteweg
; B. Binggeli
; W.K. Huchtmeier
; | Date: |
9 Jun 1997 | Subject: | astro-ph | Affiliation: | Nancay Obs., Obs. de Paris-Meudon), R.C. Kraan-Korteweg (DAEC, Obs. de Paris-Meudon), B. Binggeli (Astron. Institut Basel) and W.K. Huchtmeier (MPI fuer Radioastronomie, Bonn | Abstract: | Sensitive 21cm HI line observations were performed for 23 dwarf members and possible members of the nearby M81 group of galaxies, including five objects of a clustering of extremely low-surface brightness objects of unknown nature. With the Nancay decimetric radio telescope the radial velocity range of -529 to 1826 km/s was searched to an rms noise of ~3-5 mJy. Only three objects were detected. However, their high radial velocities (between 600 and 1150 km/s) show them to lie behind the M81 group. These three objects, classified as dS0: (UGC 4998) and Im (Kar 1N and UGC 5658), have HI masses of 0.5, 2.0 and 2.5 10^8 Msun, for the assumed distance of 4 Mpc, and HI mass-to-blue light ratios of 0.05, 0.91 and 0.22 Msun/LBsun, respectively. Considering that half of the observed objects are classified as irregular dwarfs, hence expected to be relatively gas-rich, the resulting detection rate of about 1/3 is quite low. However, the mean redshift and velocity dispersion of the M81 group ( = 101 km/s, sigma=114 km/s) suggest that the HI emission of low velocity HI-rich members of the M81 group may still remain hidden within the strong Galactic HI emission (typically -150 < v < 115 km/s) or, for the 6 dwarf candidates in the immediate vicinity of M81, overshadowed by the very extended HI envelope encompassing M81, M82, NGC 3077, and NGC 2976 (-280 < v < 355 km/s). | Source: | arXiv, astro-ph/9706081 | Services: | Forum | Review | PDF | Favorites |
|
|
No review found.
Did you like this article?
Note: answers to reviews or questions about the article must be posted in the forum section.
Authors are not allowed to review their own article. They can use the forum section.
browser Mozilla/5.0 AppleWebKit/537.36 (KHTML, like Gecko; compatible; ClaudeBot/1.0; +claudebot@anthropic.com)
|
| |
|
|
|
| News, job offers and information for researchers and scientists:
| |