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Probing Cosmic Reionization and Molecular Gas Growth with TIME

Sun, G. and Chang, T.-C. and Uzgil, B. D. and Bock, J. J. and Bradford, C. M. and Butler, V. and Caze-Cortes, T. and Cheng, Y.-T. and Cooray, A. and Crites, A. T. and Hailey-Dunsheath, S. and Emerson, N. and Frez, C. and Hoscheit, B. L. and Hunacek, J. and Keenan, R. P. and Li, C. T. and Madonia, P. and Marrone, D. P. and Moncelsi, L. and Shiu, C. and Trumper, I. and Turner, A. and Weber, A. and Wei, T. S. and Zemcov, M. (2021) Probing Cosmic Reionization and Molecular Gas Growth with TIME. Astrophysical Journal, 915 (1). Art. No. 33. ISSN 0004-637X. doi:10.3847/1538-4357/abfe62.

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Line intensity mapping (LIM) provides a unique and powerful means to probe cosmic structures by measuring the aggregate line emission from all galaxies across redshift. The method is complementary to conventional galaxy redshift surveys that are object based and demand exquisite point-source sensitivity. The Tomographic Ionized-carbon Mapping Experiment (TIME) will measure the star formation rate during cosmic reionization by observing the redshifted [C II] 158 μm line (6 ≾ z ≾ 9) in the LIM regime. TIME will simultaneously study the abundance of molecular gas during the era of peak star formation by observing the rotational CO lines emitted by galaxies at 0.5 ≾ z ≾ 2. We present the modeling framework that predicts the constraining power of TIME on a number of observables, including the line luminosity function and the auto- and cross-correlation power spectra, including synergies with external galaxy tracers. Based on an optimized survey strategy and fiducial model parameters informed by existing observations, we forecast constraints on physical quantities relevant to reionization and galaxy evolution, such as the escape fraction of ionizing photons during reionization, the faint-end slope of the galaxy luminosity function at high redshift, and the cosmic molecular gas density at cosmic noon. We discuss how these constraints can advance our understanding of cosmological galaxy evolution at the two distinct cosmic epochs for TIME, starting in 2021, and how they could be improved in future phases of the experiment.

Item Type:Article
Related URLs:
URLURL TypeDescription Paper
Sun, G.0000-0003-4070-497X
Chang, T.-C.0000-0001-5929-4187
Uzgil, B. D.0000-0001-8526-3464
Bock, J. J.0000-0002-5710-5212
Bradford, C. M.0000-0001-5261-7094
Cheng, Y.-T.0000-0002-5437-0504
Cooray, A.0000-0002-3892-0190
Hailey-Dunsheath, S.0000-0002-8504-7988
Marrone, D. P.0000-0002-2367-1080
Moncelsi, L.0000-0002-4242-3015
Zemcov, M.0000-0001-8253-1451
Additional Information:© 2021. The American Astronomical Society. Received 2020 December 16; revised 2021 May 4; accepted 2021 May 4; published 2021 July 1. We would like to thank the anonymous referees for their comments that improved the manuscript. We are indebted to Lluis Mas-Ribas for helpful comments on an early version of the paper and to Lin Yan for discussion on the [C ii] luminosity function measured from the ALPINE survey. We are also grateful to Garrett (Karto) Keating for compiling the observational constraints on molecular gas density. T.C.C. and G.S. acknowledge support from the JPL Strategic R&TD awards. A.C. acknowledges support from NSF AST-1313319 and 2015–2016 UCI Office of Research Seed Funding Award. D.P.M. and R.P.K. were supported by the National Science Foundation through CAREER grant AST-1653228. R.P.K. was supported by the National Science Foundation through Graduate Research Fellowship grant DGE-1746060. A.T.C. was supported by a KISS postdoctoral fellowship and a National Science Foundation Astronomy and Astrophysics Postdoctoral Fellowship under grant No. 1602677. This work is supported by National Science Foundation award number 1910598. Part of the research described in this paper was carried out at the Jet Propulsion Laboratory, California Institute of Technology, under a contract with the National Aeronautics and Space Administration. Software: ares (Mirocha et al. 2017), corner (Foreman-Mackey 2016), emcee (Foreman-Mackey et al. 2013), matplotlib (Hunter 2007), numpy (Walt et al. 2011), pygtc (Bocquet & Carter 2016), and scipy (Jones et al. 2001).
Group:Astronomy Department, Keck Institute for Space Studies
Funding AgencyGrant Number
JPL Research and Technology Development FundUNSPECIFIED
University of California, IrvineUNSPECIFIED
NSF Graduate Research FellowshipDGE-1746060
Keck Institute for Space Studies (KISS)UNSPECIFIED
NSF Astronomy and Astrophysics FellowshipAST-1602677
Subject Keywords:Reionization; Interstellar medium; Molecular gas; Large-scale structure of the universe; Observational cosmology; High-redshift galaxies
Issue or Number:1
Classification Code:Unified Astronomy Thesaurus concepts: Reionization (1383); Interstellar medium (847); Molecular gas (1073); Large-scale structure of the universe (902); Observational cosmology (1146); High-redshift galaxies (734)
Record Number:CaltechAUTHORS:20210224-085555089
Persistent URL:
Official Citation:G. Sun et al 2021 ApJ 915 33
Usage Policy:No commercial reproduction, distribution, display or performance rights in this work are provided.
ID Code:108164
Deposited By: Tony Diaz
Deposited On:24 Feb 2021 20:40
Last Modified:08 Jul 2021 21:18

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