Details on the event


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Astrophysics Talk

Molecular gas in galaxies in dense Mpc-scale environments through cosmic time: from the filaments to the cluster cores

Gianluca Castignani (École Polytechnique Fédérale de Lausanne)

Tuesday 16/07/2019 @ 14:00, Sala IV piano Battiferro

Numerous studies have shown that the environment is a key factor in governing the SFRs of galaxies. However the underlying physical processes are not yet well identified. I investigate the role of dense environments in processing molecular gas of galaxies from the cores out to the outskirts and filaments of distant galaxy clusters, before they fall onto the cluster cores. 1) I will present the recent analysis study of a large sample of luminous infrared galaxies (LIRGs) observed in CO with NOEMA. These galaxies belong to distant clusters at z=0.2-0.5 and were selected from the LoCuSS and MACS surveys. Existing FIR to UV photometry allowed accurate spectral energy distribution analysis. Molecular gas masses, SFRs, depletion times have been estimated. I will show how LIRGs are affected by the cluster environmements out to 2 virial radii, and how they differ from the general cluster galaxy population. 2) I also present new IRAM-30m results of a large search for CO in 7 distant brightest cluster galaxies (BCGs, Mstar>~1e+11 Msun) from z=0.4 to 2.6 selected within the DES SN deep fields as well as the COSMOS and SpARCS surveys. Our results increase by a factor of ~3 the number of distant BCGs observed in CO. I will discuss how BCGs properties are impacted by the cluster environmement through lookback time.