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21-cm H I emission from the Damped Lyman-alpha absorber SBS 1543+593

David V. Bowen·Walter Huchtmeier·Elias Brinks·Todd M. Tripp·Edward B. Jenkins
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Abstract

We detect 21-cm emission from the Low Surface Brightness (LSB) galaxy SBS 1543+593, which gives rise to a Damped Lyman-alpha (DLA) absorption line in the spectrum of the background QSO HS 1543+5921 (z=0.807). We obtain an accurate measure of the velocity of the H I gas in the LSB galaxy, v=2868 km/s, and derive a mass of 1.3e9 solar masses. We compare this value with limits obtained towards two other z~0.1 DLA systems, and show that SBS 1543+593 would not have been detected. Hence LSB galaxies similar to SBS 1543+593 can be responsible for DLA systems at even modest redshifts without being detectable from their 21-cm emission.

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David V. Bowen, Walter Huchtmeier, Elias Brinks, Todd M. Tripp, Edward B. Jenkins. 2001-04-24. 21-cm H I emission from the Damped Lyman-alpha absorber SBS 1543+593. https://doi.org/10.1051/0004-6361%3A20010592

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