Atacama Large Aperture Submillimeter Telescope (AtLAST) science: Gas and dust in nearby galaxies

Daizhong Liu; Amelie Saintonge; Caroline Bot; Francisca Kemper; Enrique Lopez-Rodriguez; Matthew W. L. Smith; Thomas Stanke; Paola Andreani; Alessandro Boselli; Claudia Cicone; Timothy A. Davis; Bendix Hagedorn; Akhil Lasrado; Ann Mao; Serena Viti; Mark Booth; Pamela Klaassen; Tony Mroczkowski; Frank Bigiel; Melanie Chevance; Martin A. Cordiner; Luca Di Mascolo; Doug Johnstone; Minju M. Lee; Thomas Maccarone; Alexander E. Thelen; Eelco van Kampen; Sven Wedemeyer

arXiv · 2403.01202

Atacama Large Aperture Submillimeter Telescope (AtLAST) science: Gas and dust in nearby galaxies

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Abstract

Understanding the physical processes that regulate star formation and galaxy evolution are major areas of activity in modern astrophysics. Nearby galaxies offer unique opportunities to inspect interstellar medium (ISM), star formation (SF), radiative, dynamic and magnetic physics in great detail from sub-galactic (kpc) scales to sub-cloud (sub-pc) scales, from quiescent galaxies to starbursts, and from field galaxies to overdensities. In this case study, we discuss the major breakthroughs in this area of research that will be enabled by the Atacama Large Aperture Submillimeter Telescope (AtLAST), a proposed 50-m single-dish submillimeter telescope. The new discovery space of AtLAST comes from its exceptional sensitivity, in particular to extended low surface brightness emission, a very large 2 degree field of view, and correspondingly high mapping efficiency. This paper focuses on four themes which will particularly benefit from AtLAST: 1) the LMC and SMC, 2) extragalactic magnetic fields, 3) the physics and chemistry of the interstellar medium, and 4) star formation and galaxy evolution. With ~1000-2000h surveys each, AtLAST could deliver deep dust continuum maps of the entire LMC and SMC fields at parsec-scale resolution, high-resolution maps of the magnetic field structure, gas density, temperature and composition of the dense and diffuse ISM in ~100 nearby galaxies, as well as the first large-scale blind CO survey in the nearby Universe, delivering molecular gas masses for up to 10^6 galaxies (3 orders of magnitude more than current samples). Through such observing campaigns, AtLAST will have a profound impact on our understanding of the baryon cycle and star formation across a wide range of environments.

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Daizhong Liu, Amelie Saintonge, Caroline Bot, Francisca Kemper, Enrique Lopez-Rodriguez, Matthew W. L. Smith, Thomas Stanke, Paola Andreani, Alessandro Boselli, Claudia Cicone, Timothy A. Davis, Bendix Hagedorn, Akhil Lasrado, Ann Mao, Serena Viti, Mark Booth, Pamela Klaassen, Tony Mroczkowski, Frank Bigiel, Melanie Chevance, Martin A. Cordiner, Luca Di Mascolo, Doug Johnstone, Minju M. Lee, Thomas Maccarone, Alexander E. Thelen, Eelco van Kampen, Sven Wedemeyer. 2024-03-02. Atacama Large Aperture Submillimeter Telescope (AtLAST) science: Gas and dust in nearby galaxies. https://arxiv.org/abs/2403.01202

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