| | |
| | |
Stat |
Members: 3665 Articles: 2'599'751 Articles rated: 2609
23 January 2025 |
|
| | | |
|
Article overview
| |
|
The HI content of star-forming galaxies at z = 0.24 | Philip Lah
; Jayaram N. Chengalur
; Frank H. Briggs
; Matthew Colless
; Roberto De Propris
; Michael B. Pracy
; W. J. G. de Blok
; Shinobu S. Fujita
; Masaru Ajiki
; Yasuhiro Shioya
; Tohru Nagao
; Takashi Murayama
; Yoshiaki Taniguchi
; Masafumi Yagi
; Sadanori Okamura
; | Date: |
24 Jan 2007 | Abstract: | We use observations from the Giant Metrewave Radio Telescope (GMRT) to measure the atomic hydrogen gas content of star-forming galaxies at z = 0.24 (i.e. a look-backtime of ~3 Gyr). The sample of galaxies studied were selected from Halpha-emitting field galaxies detected in a narrow-band imaging survey with the Subaru Telescope. The Anglo-Australian Telescope was used to obtain precise optical redshifts for these galaxies. We then coadded the HI 21 cm emission signal for all the galaxies within the GMRT spectral line data cube. From the coadded signal of 121 galaxies, we measure an average atomic hydrogen gas mass of (2.26 +- 0.90)*10^9 solar masses. We translate this HI signal into a cosmic density of neutral gas at z = 0.24 of Omega_gas = (0.91 +- 0.42)*10^-3. This is the current highest redshift at which Omega_gas has been constrained from 21 cm emission and our value is consistent with that estimated from damped Lyman-alpha systems around this redshift. We also find that the correlations between the Halpha luminosity and the radio continuum luminosity and between the star formation rate and the HI gas content in star-forming galaxies at z = 0.24 are consistent with the correlations found at z = 0. These two results suggest that the star formation mechanisms in field galaxies ~3 Gyr ago were not substantially different from the present, even though the star formation rate is 3 times higher. | Source: | arXiv, astro-ph/0701668 | 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.
|
| |
|
|
|