"The Hidden Universe": linking the evolution of dusty star formation and gas consumption across cosmic time

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Over half of the star formation energy generation in the Universe is extincted at optical wavelengths and enshrouded by dust which absorbs and re-radiates the starlight in the far-infrared/submm; and the 850&450um atmospheric windows allow us to access the redshifted far-infrared emission from this "hidden side" of galaxy formation and evolution. The James Clerk Maxwell Telescope (JCMT) Cosmology Legacy Survey (S2CLS; Geach et al. 2017) and its extension via the SCUBA-2 COSMOS survey (S2COSMOS; Simpson et al. 2017) and STUDIES (Wang et al. 2017) are the largest and most sensitive and ambitious surveys at 850 and 450 micron (in the submm wavebands) ever conducted. These unprecedented legacy surveys have yielded thousands of high-redshift galaxies selected in the sub millimetre wavebands - providing an order-of-magnitude improvement in the sample sizes of previous surveys at these wavelengths!This project will involve making measurements of the submm emission from distant galaxy populations to estimate not only the obscured star formation rate of the galaxies but also the mass of cold gas contained within them fuelling the on-going star formation in a remarkably clean way over a large span of cosmic history. This project will adopt a unique cutting-edge approach, cross-correlating the S2CLS and S2COSMOS and STUDIES2 data with very deep optical/near-infrared galaxy catalogues to explore the evolution of star formation and gas consumption across cosmic time and comparing the results to state-of-the-art models, such as EAGLE. A key theme will thus include measuring the evolution of the ISM mass over redshift and how this depends on galaxy properties such as mass and environment, as well as other galaxy properties like AGN activity. We are involved in ongoing efforts to perform detailed follow-up of these high-z submm-detected sources at higher resolution with the Atacama Large Millimetre Array (ALMA) situated at 5000m on the Chajnantor plateau in Chile, and the findings of this work will feed into new ALMA telescope proposals. There will also be an opportunity to travel to the JCMT in Hawaii to help out with observing campaigns for related submm science led by astronomers in this supervisory team.