Publikationsdatum:
2014-06-20
Beschreibung:
We report a deep search for redshifted H i 21 cm emission from three damped and sub-damped Lyman α absorbers (DLAs) at z 0.1 with the Green Bank Telescope (GBT). No evidence for a redshifted H i 21 cm emission signal was obtained in the GBT spectra of two absorbers, with the data on the third rendered unusable by terrestrial interference. The non-detections of H i 21 cm emission yield strong constraints on the H i masses of the associated galaxies, M H i 〈 2.3 x 10 9 x ( V/100) 1/2 M for the sub-DLA at z = 0.0830 towards J1553+3548 and M H i 〈 2.7 x 10 9 x ( V/100) 1/2 M for the DLA at z = 0.0963 towards J1619+3342, where V is the H i 21 cm line width, in km s –1 . This continues the trend of low H i masses found in all low- z DLAs and sub-DLAs that have been searched for redshifted H i 21 cm emission. Low-redshift absorbers with relatively low H i column densities, few x 10 20 cm –2 , thus do not typically arise in massive gas-rich galaxies.
Print ISSN:
1745-3925
Digitale ISSN:
1745-3933
Thema:
Physik
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