SPT 0538-50: Physical conditions in the interstellar medium of a strongly lensed dusty star-forming galaxy at z = 2.8

M. S. Bothwell, J. E. Aguirre, S. C. Chapman, Daniel P Marrone, J. D. Vieira, M. L N Ashby, M. Aravena, B. A. Benson, J. J. Bock, C. M. Bradford, M. Brodwin, J. E. Carlstrom, T. M. Crawford, C. De Breuck, T. P. Downes, C. D. Fassnacht, A. H. Gonzalez, T. R. Greve, B. Gullberg, Y. HezavehG. P. Holder, W. L. Holzapfel, E. Ibar, R. Ivison, J. Kamenetzky, R. Keisler, R. E. Lupu, J. Ma, M. Malkan, V. McIntyre, E. J. Murphy, H. T. Nguyen, C. L. Reichardt, M. Rosenman, J. S. Spilker, B. Stalder, A. A. Stark, M. Strandet, J. Vernet, A. Weiß, N. Welikala

Research output: Contribution to journalArticle

28 Scopus citations

Abstract

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.

Original languageEnglish (US)
Article number67
JournalAstrophysical Journal
Volume779
Issue number1
DOIs
Publication statusPublished - Dec 10 2013

    Fingerprint

Keywords

  • galaxies: evolution
  • galaxies: formation
  • galaxies: high-redshift
  • galaxies: individual
  • gravitational lensing: strong
  • submillimeter: galaxies

ASJC Scopus subject areas

  • Space and Planetary Science
  • Astronomy and Astrophysics

Cite this