2013/09/12 by M. S. Bothwell, J. E. Aguirre, James Aguirre +53 · 2 citations
Physics and Astronomy · #Astronomy #Astrophysical Phenomena and Observations #Astrophysics #Astrophysics and Star Formation Studies #Galaxies: Formation, Evolution, Phenomena #Galaxy #Interstellar medium #Luminosity #Millimeter #Physics #Redshift #Star formation #astro-ph.CO
paper · pdf · doi:10.1088/0004-637x/779/1/67
16 pages, 11 figures. Accepted for publication in ApJ
arxiv created 2013/09/12 · openalex publication_date 2013/11/26 · arxiv updated 2015/06/17 · openalex created_date 2016/06/24 · openalex updated_date 2026/08/05
We present observations of SPT-S J053816−5030.8, a gravitationally lensed dusty star-forming galaxy (DSFG) at z = 2.7817 that was first discovered at millimeter wavelengths by the South Pole Telescope. SPT 0538−50 is typical of the brightest sources found by wide-field millimeter-wavelength surveys, being lensed by an intervening galaxy at moderate redshift (in this instance, at z = 0.441). We present a wide array of multi-wavelength spectroscopic and photometric data on SPT 0538−50, including data from ALMA, Herschel PACS and SPIRE, Hubble , Spitzer , the Very Large Telescope, ATCA, APEX, and the Submillimeter Array. We use high-resolution imaging from the Hubble Space Telescope to de-blend SPT 0538−50, separating DSFG emission from that of the foreground lens. Combined with a source model derived from ALMA imaging (which suggests a magnification factor of 21 ± 4), we derive the intrinsic properties of SPT 0538−50, including the stellar mass, far-IR luminosity, star formation rate, molecular gas mass, and—using molecular line fluxes—the excitation conditions within the interstellar medium. The derived physical properties argue that we are witnessing compact, merger-driven star formation in SPT 0538−50 similar to local starburst galaxies and unlike that seen in some other DSFGs at this epoch.