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Title: Optical, Radio Continuum and HI Deep Spectroscopic Survey (ORCHIDSS)
Galaxy evolution is regulated by the continuous cycle of gas accretion, consumption and feedback. Crucial in this cycle is the availability of neutral atomic (HI) and molecular hydrogen. Our current inventory of HI, however, is very limited beyond the local Universe (z > 0.25), resulting in an incomplete picture. ORCHIDSS is designed to address this critical challenge, using the powerful combination of 4MOST spectroscopy and sensitive radio observations from the MeerKAT deep extragalactic surveys to trace the evolution of neutral gas and its lifecycle within galaxies across the bulk of cosmic history.  more » « less
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Publisher / Repository:
European Southern Observatory
Date Published:
Journal Name:
The Messenger
Page Range / eLocation ID:
Medium: X
Sponsoring Org:
National Science Foundation
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