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

Journal Article · Tue Dec 10 00:00:00 EST 2013 · Astrophysical Journal

DOI:https://doi.org/10.1088/0004-637X/779/1/67· OSTI ID:22348487

Bothwell, M. S. ^[1]; Aguirre, J. E. ^[2]; Chapman, S. C. ^[3]; Marrone, D. P. ^[4]; Vieira, J. D.; Bock, J. J.; Downes, T. P. ^[5]; Ashby, M. L. N. ^[6]; Aravena, M.; De Breuck, C.; Gullberg, B. ^[7]; Benson, B. A.; Carlstrom, J. E.; Crawford, T. M. ^[8]; Bradford, C. M. ^[9]; Brodwin, M. ^[10]; Fassnacht, C. D. ^[11]; Gonzalez, A. H. ^[12]; Greve, T. R. ^[13]; Hezaveh, Y. ^[14] ; others, and

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1. Cavendish Laboratory, University of Cambridge, JJ Thompson Avenue, Cambridge CB3 0HA (United Kingdom)
2. University of Pennsylvania, 209 South 33rd Street, Philadelphia, PA 19104 (United States)
3. Dalhousie University, Halifax, Nova Scotia (Canada)
4. Steward Observatory, University of Arizona, 933 North Cherry Avenue, Tucson, AZ 85721 (United States)
5. California Institute of Technology, 1200 East California Blvd., Pasadena, CA 91125 (United States)
6. Harvard-Smithsonian Center for Astrophysics, 60 Garden Street, Cambridge, MA 02138 (United States)
7. European Southern Observatory, Alonso de Cordova 3107, Casilla 19001 Vitacura Santiago (Chile)
8. Kavli Institute for Cosmological Physics, University of Chicago, 5640 South Ellis Avenue, Chicago, IL 60637 (United States)
9. Jet Propulsion Laboratory, 4800 Oak Grove Drive, Pasadena, CA 91109 (United States)
10. Department of Physics and Astronomy, University of Missouri, 5110 Rockhill Road, Kansas City, MO 64110 (United States)
11. Department of Physics, University of California, One Shields Avenue, Davis, CA 95616 (United States)
12. Department of Astronomy, University of Florida, Gainesville, FL 32611 (United States)
13. Department of Physics and Astronomy, University College London, Gower Street, London WC1E 6BT (United Kingdom)
14. Department of Physics, McGill University, 3600 Rue University, Montreal, Quebec H3A 2T8 (Canada)

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.

• OSTI ID: 22348487
• Journal Information: Astrophysical Journal, Vol. 779, Issue 1; Other Information: Country of input: International Atomic Energy Agency (IAEA); ISSN 0004-637X
• Country of Publication: United States
• Language: English

Related Subjects

79 ASTROPHYSICS
COSMOLOGY AND ASTRONOMY
EMISSION
EVOLUTION
EXCITATION
GALAXIES
GRAVITATIONAL LENSES
LUMINOSITY
MASS
PERTURBED ANGULAR CORRELATION
RED SHIFT
RESOLUTION
SPACE
STARS
TELESCOPES
WAVELENGTHS