The evolution of the cosmic molecular gas density

Fabian Walter; Chris Carilli; Roberto Decarli; Dominik Riechers; Manuel Aravena; Franz Erik Bauer; Frank Bertoldi; Alberto Bolatto; Leindert Boogaard; Rychard Bouwens; Denis Burgarella; Caitlin Casey; Asantha Cooray; Paolo Cortes; Pierre Cox; Emanuele Daddi; Jeremy Darling; Bjorn Emonts; Jorge Gonzalez Lopez; Jacqueline Hodge; Hanae Inami; Rob Ivison; Ely Kovetz; Olivier Le Fevre; Benjamin Magnelli; Dan Marrone; Eric Murphy; Desika Narayanan; Mladen Novak; Pascal Oesch; Riccardo Pavesi; Tanio Diaz Santos; Mark Sargent; Douglas Scott; Nick Scoville; Gordon Stacey; Jeff Wagg; Paul van der Werf; Bade Uzgil; Axel Weiss; Min Yun

arXiv · 1903.08659

The evolution of the cosmic molecular gas density

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Abstract

One of the last missing pieces in the puzzle of galaxy formation and evolution through cosmic history is a detailed picture of the role of the cold gas supply in the star-formation process. Cold gas is the fuel for star formation, and thus regulates the buildup of stellar mass, both through the amount of material present through a galaxy's gas mass fraction, and through the efficiency at which it is converted to stars. Over the last decade, important progress has been made in understanding the relative importance of these two factors along with the role of feedback, and the first measurements of the volume density of cold gas out to redshift 4, (the "cold gas history of the Universe") has been obtained. To match the precision of measurements of the star formation and black-hole accretion histories over the coming decades, a two orders of magnitude improvement in molecular line survey speeds is required compared to what is possible with current facilities. Possible pathways towards such large gains include significant upgrades to current facilities like ALMA by 2030 (and beyond), and eventually the construction of a new generation of radio-to-millimeter wavelength facilities, such as the next generation Very Large Array (ngVLA) concept.

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Fabian Walter, Chris Carilli, Roberto Decarli, Dominik Riechers, Manuel Aravena, Franz Erik Bauer, Frank Bertoldi, Alberto Bolatto, Leindert Boogaard, Rychard Bouwens, Denis Burgarella, Caitlin Casey, Asantha Cooray, Paolo Cortes, Pierre Cox, Emanuele Daddi, Jeremy Darling, Bjorn Emonts, Jorge Gonzalez Lopez, Jacqueline Hodge, Hanae Inami, Rob Ivison, Ely Kovetz, Olivier Le Fevre, Benjamin Magnelli, Dan Marrone, Eric Murphy, Desika Narayanan, Mladen Novak, Pascal Oesch, Riccardo Pavesi, Tanio Diaz Santos, Mark Sargent, Douglas Scott, Nick Scoville, Gordon Stacey, Jeff Wagg, Paul van der Werf, Bade Uzgil, Axel Weiss, Min Yun. 2019-03-20. The evolution of the cosmic molecular gas density. https://arxiv.org/abs/1903.08659

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