Abstract
We report a deep search for redshifted HI 21 cm emission from three damped
and sub-damped Lyman-$\alpha$ absorbers (DLAs) at $z 0.1$ with the
Green Bank Telescope (GBT). No evidence for a redshifted HI 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 HI
21 cm emission yield strong constraints on the HI masses of the associated
galaxies, M$_HI < 2.3 10^9 (\Delta V/100)^1/2$ M$_ødot$
for the sub-DLA at $z = 0.0830$ towards J1553+3548, and M$_HI < 2.7
10^9 (\Delta V/100)^1/2$ M$_ødot$ for the DLA at $z = 0.0963$
towards J1619+3342, where $\Delta V$ is the HI 21 cm line width, in km
s$^-1$. This continues the trend of low HI masses found in all low-$z$ DLAs
and sub-DLAs that have been searched for redshifted HI 21 cm emission.
Low-redshift absorbers with relatively low HI column densities, $few
10^20$ cm$^-2$, thus do not typically arise in massive gas-rich
galaxies.
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