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arXiv · 1809.09568

Molecular gas in radio galaxies at $z=0.4-2.6$ in (proto-)cluster environment

G. Castignani·F. Combes·P. Salomè·C. Benoist·M. Chiaberge·J. Freundlich·G. De Zotti
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Abstract

We investigate the role of the environment in processing molecular gas in radio galaxies (RGs). We observed five RGs at $z=0.4-2.6$ in dense Mpc-scale environment with the IRAM-30m telescope. We set four upper-limits and report a tentative CO(7$\rightarrow$6) detection for COSMOS-FRI 70 at $z=2.63$, which is the most distant brightest cluster galaxy (BCG) candidate detected in CO. We speculate that the cluster environment might have played a role in preventing the refueling via environmental mechanisms such as galaxy harassment, strangulation, ram-pressure, or tidal stripping. The RGs of this work are excellent targets for ALMA as well as next generation telescopes such as the James Webb Space Telescope.

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G. Castignani, F. Combes, P. Salomè, C. Benoist, M. Chiaberge, J. Freundlich, G. De Zotti. 2018-09-25. Molecular gas in radio galaxies at $z=0.4-2.6$ in (proto-)cluster environment. https://arxiv.org/abs/1809.09568

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