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GMRT Detection of HI 21 cm-line Absorption from the Peculiar Galaxy in Abell 2125

K. S. Dwarakanath·F. N. Owen
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Abstract

Using the recently completed Giant Meterwave Radio Telescope, we have detected the HI 21 cm-line absorption from the peculiar galaxy C153 in the galaxy cluster Abell 2125. The HI absorption is at a redshift of 0.2533, with a peak optical depth of 0.36. The full width at half minimum of the absorption line is 100 km/s. The estimated column density of atomic Hydrogen is 0.7e22(Ts/100K) per sq. cm. The HI absorption is redshifted by ~ 400 km/s compared to the [OIII] emission line from this system. We attribute this to an in-falling cold gas, or to an out-flowing ionised gas, or to a combination of both as a consequence of tidal interactions of C153 with either a cluster galaxy or the cluster potential.

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K. S. Dwarakanath, F. N. Owen. 2001-06-07. GMRT Detection of HI 21 cm-line Absorption from the Peculiar Galaxy in Abell 2125. https://doi.org/10.1007/bf02933586

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