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arXiv · 1903.04119

C IV absorbers tracing cool gas in dense galaxy group/cluster environments

Aditya Manuwal·Anand Narayanan·Sowgat Muzahid·Jane C. Charlton·Vikram Khaire·Hum Chand
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Abstract

We present analysis on three intervening H I-C IV absorption systems tracing gas within galaxy group/cluster environments, identified in the $HST$/COS far-UV spectra of the background quasars PG $1148+549$ ($z_{abs}=0.00346$), SBS~$1122+594$ ($z_{abs}=0.00402$) and RXJ~$1230.8+0115$ ($z_{abs}=0.00574$). The ionization models are consistent with the origin of metal lines and H I from a cool and diffuse photoionized gas phase with $T \lesssim 4 \times 10^{4}$ K and $n_{\mathrm{H}} \lesssim 5 \times 10^{-4}$ cm$^{-3}$. The three absorbers have $89$, $51$ and $17$ galaxies detected within $1$ Mpc and $|\Delta v| < 600$ km s$^{-1}$. The RXJ~$1230.8+0115$ sightline traces the outskirt regions of the Virgo cluster where the absorber is found to have super-solar metallicity. The detection of metal lines along with H I has enabled us to confirm the presence of cool, diffuse gas possibly enriched by outflows and tidal interactions in environments with significant galaxy density.

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Aditya Manuwal, Anand Narayanan, Sowgat Muzahid, Jane C. Charlton, Vikram Khaire, Hum Chand. 2019-03-11. C IV absorbers tracing cool gas in dense galaxy group/cluster environments. https://doi.org/10.1093/mnras/stz195

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