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Virgo filaments: I. Processing of gas in cosmological filaments around the Virgo cluster
It is now well established that galaxies have different morphologies, gas contents, and star formation rates (SFR) in dense environments like galaxy clusters. The impact of environmental density extends to several virial radii, and galaxies appear to be pre-processed in filaments and groups before falling into the cluster. Our goal is to quantify this pre-processing in terms of gas content and SFR, as a function of density in cosmic filaments. We have observed the two first CO transitions in 163 galaxies with the IRAM-30 m telescope, and added 82 more measurements from the literature, thus forming a sample of 245 galaxies in the filaments around the Virgo cluster. We gathered HI-21cm measurements from the literature and observed 69 galaxies with the Nançay telescope to complete our sample. We compare our filament galaxies with comparable samples from the Virgo cluster and with the isolated galaxies of the AMIGA sample. We find a clear progression from field galaxies to filament and cluster galaxies for decreasing SFR, increasing fraction of galaxies in the quenching phase, an increasing proportion of early-type galaxies, and decreasing gas content. Galaxies in the quenching phase, defined as having a SFR below one-third of that of the main sequence more »
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NSF-PAR ID:
10320959
Journal Name:
Astronomy & Astrophysics
Volume:
657
ISSN:
0004-6361
National Science Foundation
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