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arXiv · 0910.4427

HI gas in the rejuvenated radio galaxy 4C29.30

Yogesh Chandola·D. J. Saikia·Neeraj Gupta
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Abstract

We report the results of our observations of HI absorption towards the central region of the rejuvenated radio galaxy 4C29.30 (J0840+2949) with the Giant Metrewave Radio Telescope (GMRT). The radio source has diffuse, extended emission with an angular size of $\sim$520 arcsec (639 kpc) within which a compact edge-brightened double-lobed source with a size of 29 arcsec (36 kpc) is embedded. The absorption profile which is seen towards the central component of the inner double is well resolved and consists of six components; all but one of which appears to be red-shifted relative to the optical systemic velocity. The neutral hydrogen column density is estimated to be $N$(HI)=4.7$\times10^{21}$($T_s$/100)($f_c$/1.0) cm$^{-2}$, where $T_s$ and $f_c$ are the spin temperature and covering factor of the background source respectively. This detection reinforces a strong correlation between the occurrence of HI absorption and rejuvenation of radio activity suggested earlier, with the possibility that the red-shifted gas is fuelling the recent activity.

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Yogesh Chandola, D. J. Saikia, Neeraj Gupta. 2009-10-23. HI gas in the rejuvenated radio galaxy 4C29.30. https://doi.org/10.1111/j.1365-2966.2009.15854.x

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