ECOology for Galaxies using ALMA archive and Legacy surveys

Galaxy formation and evolution are intimately connected to the galaxy's surrounding environment and its halo. Baryonic components other than stellar mass, including interstellar medium (ISM) and circum-galactic medium (CGM) must be better constrained in different environments in order to fully characterise the relation between baryon and halo, which is fundamental concerning galaxy evolution in a cosmological context.I propose a project ECOGAL (ECOology for Galaxies using ALMA archive and Legacy surveys) that leverages the 10-year repository of the ALMA archive to constrain cosmic molecular gas density and investigate CGM in different phases (cold and hot) for several (proto)cluster systems at redshift greater than 1. With the complete dust and FIR line emission catalogue from the ALMA archive within optical/infrared(IR) legacy survey fields, ECOGAL will i) constrain cosmic gas density beyond redshift 1 with unarguably better number statistics; and ii) build a first representative sample on CGM properties in (proto)clusters at z=1-3, through carbon and carbon monoxide line emissions (cold phase) and thermal Sunyaev-Zel’dovich (tSZ) effect signals (hot phase).With the timely convergence with current and next-generation optical/IR facilities (JWST, Euclid, the Vera Rubin observatory) and a decade-old ALMA archive at submm/mm, the outcome of ECOGAL will produce a state-of-the-art reference to studies of galaxy formation and evolution in a large-scale structure. The Cosmic Dawn Center (DAWN) and DTU space have extensive access to the most advanced optical/IR facilities and extragalactic surveys and offer the necessary computing resources and research environment.Therefore, they are the optimal places to carry out this project. The expertise of G. Magdis and his group support is also essential to make this proposal successful.