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arXiv · 1912.10948

The Star Formation Rate of Massive Dusty Galaxies at Early Cosmic Times

Abstract

We explore how the estimated star formation rate (SFR) of a sample of isolated, massive dusty star-forming galaxies at early cosmic epochs ($1.5 < z < 3.5$) changes when their ultraviolet (UV) to near-infrared (NIR) spectral energy distribution is extended to longer wavelengths by adding far-infrared/sub-millimeter data to trace the reprocessed radiation from dust heated by young massive stars. We use large-area surveys with multi-wavelength datasets that include DECam UV-to-optical, VICS82 NIR, Spitzer-IRAC NIR, and Herschel-SPIRE far-infrared/sub-millimeter data. We find that the inclusion of far-infrared/sub-millimeter data leads to SFRs that span $\sim$100-3500 $M_{\odot} yr^{-1}$ and are higher than the extinction-corrected UV-based SFR by an average factor of $\sim$3.5, and by a factor of over 10 in many individual galaxies. Our study demonstrates the importance of far-IR/sub-millimeter data for deriving accurate SFRs in massive dusty galaxies at early epochs, and underscores the need for next-generation far-IR/sub-millimeter facilities with high sensitivity, field of view, and angular resolution.

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Zacharias E. Escalante, Shardha Jogee, Sydney Sherman. 2019-12-23. The Star Formation Rate of Massive Dusty Galaxies at Early Cosmic Times. https://arxiv.org/abs/1912.10948

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