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arXiv · 1705.07912

ISM properties of a Massive Dusty Star-Forming Galaxy discovered at z ~ 7

M. L. Strandet·A. Weiß·C. De Breuck·D. P. Marrone·J. D. Vieira·M. Aravena·M. L. N. Ashby·M. Béthermin·M. S. Bothwell·C. M. Bradford·J. E. Carlstrom·S. C. Chapman·D. J. M. Cunningham·Chian-Chou Chen·C. D. Fassnacht·A. H. Gonzalez·T. R. Greve·B. Gullberg·C. C. Hayward·Y. Hezaveh·K. Litke·J. Ma·M. Malkan·K. M. Menten·T. Miller·E. J. Murphy·D. Narayanan·K. A. Phadke·K. M. Rotermund·J. S. Spilker·J. Sreevani
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Abstract

We report the discovery and constrain the physical conditions of the interstellar medium of the highest-redshift millimeter-selected dusty star-forming galaxy (DSFG) to date, SPT-S J031132-5823.4 (hereafter SPT0311-58), at $z=6.900 +/- 0.002$. SPT0311-58 was discovered via its 1.4mm thermal dust continuum emission in the South Pole Telescope (SPT)-SZ survey. The spectroscopic redshift was determined through an ALMA 3mm frequency scan that detected CO(6-5), CO(7-6) and [CI](2-1), and subsequently confirmed by detections of CO(3-2) with ATCA and [CII] 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 [CI] 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 $M_{\rm gas} = 3.3 \pm 1.9 \times10^{11}\,M_{\odot}$. Its large mass and intense star formation is very rare for a source well into the Epoch of Reionization.

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M. L. Strandet, A. Weiß, C. De Breuck, D. P. Marrone, J. D. Vieira, M. Aravena, M. L. N. Ashby, M. Béthermin, M. S. Bothwell, C. M. Bradford, J. E. Carlstrom, S. C. Chapman, D. J. M. Cunningham, Chian-Chou Chen, C. D. Fassnacht, A. H. Gonzalez, T. R. Greve, B. Gullberg, C. C. Hayward, Y. Hezaveh, K. Litke, J. Ma, M. Malkan, K. M. Menten, T. Miller, E. J. Murphy, D. Narayanan, K. A. Phadke, K. M. Rotermund, J. S. Spilker, J. Sreevani. 2017-05-22. ISM properties of a Massive Dusty Star-Forming Galaxy discovered at z ~ 7. https://doi.org/10.3847/2041-8213%2Faa74b0

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