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arXiv · 2508.20276

HI gas in the rejuvenated radio galaxy PKS 2014-55

Leon Mtshweni·Kshitij Thorat·Roger P. Deane·Bradley S. Frank·Filippo M. Maccagni·Gyula I. J'ozsa·William D. Cotton·Gourab Giri·Sarah V. White·Marcellin Atemkeng·Hertzog L. Bester·Bernie L. Fanaroff·Ian Heywood·Graham Lawrie·Thato E. Manamela·Isaac Magolego·Tom Mauch·Nadeem Oozeer·Oleg Smirnov·Masacheba S. Kupa
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Abstract

We present new high-spectral-resolution MeerKAT observations of $\mathrm{HI}$ absorption against the central region of the restarted, giant, X-shaped radio galaxy PKS2014-55, which exhibits morphological evidence of three distinct cycles of activity. We report a wide component $(\mathrm{FWHM}=38 \pm 7~\mathrm{kms^{-1}})$ redshifted to $96 \pm 50~\mathrm{kms^{-1}}$, a deep narrow detection $(\mathrm{FWHM}=19 \pm 6~\mathrm{kms^{-1}})$ redshifted to $160 \pm 40~\mathrm{kms^{-1}}$, and a shallow component $(\mathrm{FWHM}=22 \pm 6~\mathrm{kms^{-1}})$ redshifted to $240 \pm 40~\mathrm{kms^{-1}}$. One of the three components exceeds the typical rotational velocity of $100~\mathrm{kms^{-1}}$, suggesting complex kinematics of the inflowing gas. These $\mathrm{HI}$ observations support the correlation between the occurrence of $\mathrm{HI}$ absorption and the rejuvenation of radio activity.

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Leon Mtshweni, Kshitij Thorat, Roger P. Deane, Bradley S. Frank, Filippo M. Maccagni, Gyula I. J'ozsa, William D. Cotton, Gourab Giri, Sarah V. White, Marcellin Atemkeng, Hertzog L. Bester, Bernie L. Fanaroff, Ian Heywood, Graham Lawrie, Thato E. Manamela, Isaac Magolego, Tom Mauch, Nadeem Oozeer, Oleg Smirnov, Masacheba S. Kupa. 2025-08-27. HI gas in the rejuvenated radio galaxy PKS 2014-55. https://doi.org/10.1093/mnras%2Fstaf1452

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