BLIND DETECTIONS OF CO J = 1-0 IN 11 H-ATLAS GALAXIES AT z = 2.1-3.5 WITH THE GBT/ZPECTROMETER

Journal Article · Wed Jun 20 00:00:00 EDT 2012 · Astrophysical Journal

DOI:https://doi.org/10.1088/0004-637X/752/2/152· OSTI ID:22036977

Harris, A I ^[1]; Baker, A J ^[2]; Frayer, D T ^[3]; Smail, Ian; Swinbank, A M ^[4]; Riechers, D A ^[5]; Van der Werf, P P ^[6]; Auld, R; Dariush, A; Eales, S ^[7]; Baes, M ^[8]; Bussmann, R S ^[9]; Buttiglione, S; De Zotti, G ^[10]; Cava, A ^[11]; Clements, D L ^[12]; Cooray, A ^[13]; Dannerbauer, H ^[14]; Dunne, L ^[15]; Dye, S ^[16] ; others, and

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1. Department of Astronomy, University of Maryland, College Park, MD 20742 (United States)
2. Department of Physics and Astronomy, Rutgers, The State University of New Jersey, Piscataway, NJ 08854-8019 (United States)
3. National Radio Astronomy Observatory, P.O. Box 2, Green Bank, WV 24944 (United States)
4. Institute for Computational Cosmology, Department of Physics, Durham University, South Road, Durham DH1 3LE (United Kingdom)
5. Astronomy Department, California Institute of Technology, MC 249-17, 1200 East California Boulevard, Pasadena, CA 91125 (United States)
6. Leiden Observatory, Leiden University, P.O. Box 9513, NL-2300 RA Leiden (Netherlands)
7. School of Physics and Astronomy, Cardiff University, 5 The Parade, Cardiff CF24 3AA (United Kingdom)
8. Sterrenkundig Observatorium, Universiteit Gent, Krijgslaan 281 S9, B-9000 Gent (Belgium)
9. Harvard-Smithsonian CfA, 60 Garden Street, MS 78, Cambridge, MA 02138 (United States)
10. INAF-Osservatorio Astronomico di Padova, Vicolo Osservatorio, I-35122 Padova (Italy)
11. Departamento de Astrofisica, Facultad de CC. Fisicas, Universidad Complutense de Madrid, E-28040 Madrid (Spain)
12. Physics Department, Imperial College London, South Kensington Campus, SW7 2AZ (United Kingdom)
13. Department of Physics and Astronomy, University of California, Irvine, CA 92697 (United States)
14. Institut fuer Astronomie, Universitaet Wien, Tuerkenschanzstrasse 17, 1180 Wien (Austria)
15. Department of Physics and Astronomy, University of Canterbury, Private Bag 4800, Christchurch 8140 (New Zealand)
16. School of Physics and Astronomy, University of Nottingham, Nottingham NG7 2RD (United Kingdom)

We report measurements of the carbon monoxide ground state rotational transition ({sup 12}C{sup 16}O J = 1-0) with the Zpectrometer ultrawideband spectrometer on the 100 m diameter Green Bank Telescope. The sample comprises 11 galaxies with redshifts between z = 2.1 and 3.5 from a total sample of 24 targets identified by Herschel-ATLAS photometric colors from the SPIRE instrument. Nine of the CO measurements are new redshift determinations, substantially adding to the number of detections of galaxies with rest-frame peak submillimeter emission near 100 {mu}m. The CO detections confirm the existence of massive gas reservoirs within these luminous dusty star-forming galaxies (DSFGs). The CO redshift distribution of the 350 {mu}m selected galaxies is strikingly similar to the optical redshifts of 850 {mu}m-selected submillimeter galaxies in 2.1 {<=} z {<=} 3.5. Spectroscopic redshifts break a temperature-redshift degeneracy; optically thin dust models fit to the far-infrared photometry indicate characteristic dust temperatures near 34 K for most of the galaxies we detect in CO. Detections of two warmer galaxies, and statistically significant nondetections, hint at warmer or molecule-poor DSFGs with redshifts that are difficult to determine from Herschel-SPIRE photometric colors alone. Many of the galaxies identified by H-ATLAS photometry are expected to be amplified by foreground gravitational lenses. Analysis of CO linewidths and luminosities provides a method for finding approximate gravitational lens magnifications {mu} from spectroscopic data alone, yielding {mu} {approx} 3-20. Corrected for magnification, most galaxy luminosities are consistent with an ultraluminous infrared galaxy classification, but three are candidate hyper-LIRGs with luminosities greater than 10{sup 13} L{sub Sun }.

• OSTI ID: 22036977
• Journal Information: Astrophysical Journal, Vol. 752, Issue 2; 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
APPROXIMATIONS
ASTRONOMY
ASTROPHYSICS
CARBON MONOXIDE
COSMIC DUST
DETECTION
FAR INFRARED RADIATION
GALACTIC EVOLUTION
GALAXIES
GRAVITATIONAL LENSES
GROUND STATES
INFRARED SPECTROMETERS
LINE WIDTHS
LUMINOSITY
MOLECULES
PHOTOMETRY
PHOTON EMISSION
RED SHIFT
STARS