Welcome to the new version of CaltechAUTHORS. Login is currently restricted to library staff. If you notice any issues, please email coda@library.caltech.edu
Published July 21, 2018 | Published + Accepted Version
Journal Article Open

Submillimetre flux as a probe of molecular ISM mass in high-z galaxies


Recent long-wavelength observations on the thermal dust continuum suggest that the Rayleigh–Jeans tail can be used as a time-efficient quantitative probe of the dust and interstellar medium (ISM) mass in high-z galaxies. We use high-resolution cosmological simulations from the Feedback in Realistic Environment (FIRE) project to analyse the dust emission of M* ≳ 10^(10) M_⊙ galaxies at z = 2–4. Our simulations (MASSIVEFIRE) explicitly include various forms of stellar feedback, and they produce the stellar masses and star formation rates of high-z galaxies in agreement with observations. Using radiative transfer modelling, we show that sub-millimetre (sub-mm) luminosity and molecular ISM mass are tightly correlated and that the overall normalization is in quantitative agreement with observations. Notably, sub-mm luminosity traces molecular ISM mass even during starburst episodes as dust mass and mass-weighted temperature evolve only moderately between z = 4 and z = 2, including during starbursts. Our finding supports the empirical approach of using broadband sub-mm flux as a proxy for molecular gas content in high-z galaxies. We thus expect single-band sub-mm observations with ALMA to dramatically increase the sample size of high-z galaxies with reliable ISM masses in the near future.

Additional Information

© 2018 The Author(s) Published by Oxford University Press on behalf of the Royal Astronomical Society. This article is published and distributed under the terms of the Oxford University Press, Standard Journals Publication Model (https://academic.oup.com/journals/pages/about_us/legal/notices) Accepted 2018 April 16. Received 2018 April 14; in original form 2018 February 12. We thank the anonymous referee for comments that help improve the quality of this letter. We thank Onur Çatmabacak, Tine Colman, Nick Gnedin, Kevin Harrington, Claudia Lagos, and Desika Narayanan for valuable discussions. We thank Peter Camps for providing SSP libraries for the STARBURST99 stellar evolution model. Simulations were run with resources provided by the NASA High-End Computing (HEC) Program through the NASA Advanced Supercomputing (NAS) Division at Ames Research Center, proposal SMD-14-5492. Additional computing support was provided by HEC allocations SMD-14-5189, SMD-15-5950, and NSF XSEDE allocations AST-120025, AST-150045. RF acknowledges financial support from the Swiss National Science Foundation (grant no. 157591). CAFG was supported by NSF through grants AST-1412836, AST-1517491, AST-1715216, and CAREER award AST-1652522, and by NASA through grant NNX15AB22G. DK was supported by NSF grant AST-1715101 and the Cottrell Scholar Award from the Research Corporation for Science Advancement. EQ was supported in part by NSF grant AST-1715070 and a Simons Investigator Award from the Simons Foundation. The Flatiron Institute is supported by the Simons Foundation.

Attached Files

Published - sly071.pdf

Accepted Version - 1804.02403.pdf


Files (2.0 MB)
Name Size Download all
1.1 MB Preview Download
886.1 kB Preview Download

Additional details

August 19, 2023
October 19, 2023