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arXiv · 2009.03343

Extended radio AGN at z ~ 1 in the ORELSE survey: The confining effect of dense environments

Lu Shen·Guilin Liu·Mengfei Zhang·Brian C. Lemaux·Lori M. Lubin·Debora Pelliccia·Emily Moravec·Emmet G. Golden-Marx·Hongyan Zhou·Wenjuan Fang·Adam Tomczak·John McKean·Neal A. Miller·Christopher D. Fassnacht·Po-Feng Wu·Dale D. Kocevski·Roy R. Gal·Denise Hung·Gordon K Squires
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Abstract

Recent hydrodynamic simulations and observations of radio jets have shown that the surrounding environment has a large effect on their resulting morphology. To investigate this we use a sample of 50 Extended Radio Active Galactic Nuclei (ERAGN) detected in the Observations of Redshift Evolution in Large Scale Environments (ORELSE) survey. These sources are all successfully cross-identified to galaxies within a redshift range of $0.55 \leq z \leq 1.35$, either through spectroscopic redshifts or accurate photometric redshifts. We find that ERAGN are more compact in high-density environments than those in low-density environments at a significance level of 4.5$\sigma$. Among a series of internal properties under our scrutiny, only the radio power demonstrates a positive correlation with their spatial extent. After removing the possible radio power effect, the difference of size in low- and high-density environments persists. In the global environment analyses, the majority (86\%) of high-density ERAGN reside in the cluster/group environment. In addition, ERAGN in the cluster/group central regions are preferentially compact with a small scatter in size, compared to those in the cluster/group intermediate regions and fields. In conclusion, our data appear to support the interpretation that the dense intracluster gas in the central regions of galaxy clusters plays a major role in confining the spatial extent of radio jets.

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Lu Shen, Guilin Liu, Mengfei Zhang, Brian C. Lemaux, Lori M. Lubin, Debora Pelliccia, Emily Moravec, Emmet G. Golden-Marx, Hongyan Zhou, Wenjuan Fang, Adam Tomczak, John McKean, Neal A. Miller, Christopher D. Fassnacht, Po-Feng Wu, Dale D. Kocevski, Roy R. Gal, Denise Hung, Gordon K Squires. 2020-09-07. Extended radio AGN at z ~ 1 in the ORELSE survey: The confining effect of dense environments. https://doi.org/10.3847/1538-4357/abb5a0

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