ISM Properties of a Massive Dusty Star-forming Galaxy Discovered at z ∼ 7

• Published in: The Astrophysical Journal Letters
• Main Authors: Strandet, ML, Weiss, A, De Breuck, C, Marrone, DP, Vieira, JD, Aravena, M, Ashby, MLN, Béthermin, M, Bothwell, MS, Bradford, CM, Carlstrom, JE, Chapman, SC, Cunningham, DJM, Chen, Chian-Chou, Fassnacht, CD, Gonzalez, AH, Greve, TR, Gullberg, B, Hayward, CC, Hezaveh, Y, Litke, K, Ma, J, Malkan, M, Menten, KM, Miller, T, Murphy, EJ, Narayanan, D, Phadke, KA, Rotermund, KM, Spilker, JS, Sreevani, J
• Format: Article in Journal/Newspaper
• Language: unknown
• Published: eScholarship, University of California 2017
• Subjects: early universe; galaxies: high-redshift; galaxies: star formation; astro-ph.GA; Astronomical and Space Sciences; Astronomy & Astrophysics; South pole
• Online Access: https://escholarship.org/uc/item/1qf5k0r7; https://escholarship.org/content/qt1qf5k0r7/qt1qf5k0r7.pdf; https://doi.org/10.3847/2041-8213/aa74b0

We report the discovery and constrain the physical conditions of the interstellar medium of the highest-redshift millimeter-selected dusty star-forming galaxy to date, SPT-S J031132-5823.4 (hereafter SPT0311-58), at z = 6.900 ± 0.002. SPT0311-58 was discovered via its 1.4 mm thermal dust continuum emission in the South Pole Telescope (SPT)-SZ survey. The spectroscopic redshift was determined through an Atacama Large Millimeter/submillimeter Array 3 mm frequency scan that detected CO(6-5), CO(7-6), and [C I](2-1), and subsequently was confirmed by detections of CO(3-2) with the Australia Telescope Compact Array and [C II] with APEX. We constrain the properties of the ISM in SPT0311-58 with a radiative transfer analysis of the dust continuum photometry and the CO and [C I] line emission. This allows us to determine the gas content without ad hoc assumptions about gas mass scaling factors. SPT0311-58 is extremely massive, with an intrinsic gas mass of Mgas 3.3±1.9×1011 M. Its large mass and intense star formation is very rare for a source well into the epoch of reionization.