MOLECULAR CO(1-0) GAS IN THE z {approx} 2 RADIO GALAXY MRC 0152-209

Journal Article · Fri Jun 10 00:00:00 EDT 2011 · Astrophysical Journal Letters

DOI:https://doi.org/10.1088/2041-8205/734/1/L25· OSTI ID:21562606

Emonts, B H. C.; Feain, I; Mao, M Y; Norris, R P; Ekers, R D; Rees, G; Stevens, J B ^[1]; Miley, G; Roettgering, H J. A. ^[2]; Villar-Martin, M ^[3]; Sadler, E M ^[4]; Morganti, R; Oosterloo, T A ^[5]; Saikia, D J ^[6]

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1. CSIRO Astronomy and Space Science, Australia Telescope National Facility, P.O. Box 76, Epping NSW, 1710 (Australia)
2. Leiden Observatory, University of Leiden, P.O. Box 9513, 2300 RA Leiden (Netherlands)
3. Instituto de Astrofisica de Andalucia (CSIC), Aptdo. 3004, Granada (Spain)
4. School of Physics, University of Sydney, NSW 2006 (Australia)
5. Netherlands Institute for Radio Astronomy, Postbus 2, 7990 AA Dwingeloo (Netherlands)
6. National Centre for Radio Astrophysics, TIFR, Pune University Campus, Post Bag 3, Pune 411 007 (India)

We report the detection of molecular CO(1-0) gas in the high-z radio galaxy MRC 0152-209 (z = 1.92) with the Australia Telescope Compact Array Broadband Backend (ATCA/CABB). This is the third known detection of CO(1-0) in a high-z radio galaxy to date. CO(1-0) is the most robust tracer of the overall molecular gas content (including the widespread, low-density, and sub-thermally excited component), hence observations of CO(1-0) are crucial for studying galaxy evolution in the early universe. We derive L'{sub CO} = 6.6 {+-} 2.0 x 10{sup 10} K km s{sup -1} pc{sup 2} for MRC 0152-209, which is comparable to that derived from CO(1-0) observations of several high-z submillimeter and star-forming BzK galaxies. The CO(1-0) traces a total molecular hydrogen mass of M{sub H{sub 2}} = 5 x 10{sup 10} ({alpha}{sub x}/0.8) M{sub sun}. MRC 0152-209 is an infrared bright radio galaxy, in which a large reservoir of cold molecular gas has not (yet) been depleted by star formation or radio source feedback. Its compact radio source is reliably detected at 40 GHz and has a steep spectral index of {alpha} = -1.3 between 1.4 and 40 GHz (4-115 GHz in the galaxy's rest frame). MRC 0152-209 is part of an ongoing systematic ATCA/CABB survey of CO(1-0) in high-z radio galaxies between 1.7 < z < 3.

• OSTI ID: 21562606
• Journal Information: Astrophysical Journal Letters, Vol. 734, Issue 1; Other Information: DOI: 10.1088/2041-8205/734/1/L25; ISSN 2041-8205
• Country of Publication: United States
• Language: English

Related Subjects

46 INSTRUMENTATION RELATED TO NUCLEAR SCIENCE AND TECHNOLOGY
79 ASTROPHYSICS
COSMOLOGY AND ASTRONOMY
CARBON MONOXIDE
DETECTION
RADIO GALAXIES
CARBON COMPOUNDS
CARBON OXIDES
CHALCOGENIDES
COSMIC RADIO SOURCES
GALAXIES
OXIDES
OXYGEN COMPOUNDS