THE faint IRAS source 10214 + 4724, identified1 with a distant galaxy at redshift z = 2.286, is one of the most intrinsically luminous objects in the Universe, with L≈1014 L⊙ (whereL⊙ is the solar luminosity). The remarkable detection of emission from neutral CO (ref. 2) leads, by comparison with similar detections in nearby galaxies, to an estimate of 2–6 x 1011M⊙ for the mass of neutral molecular hydrogen in this galaxy. This is 30–90 times less than the estimate given in ref. 2, but still comparable to the total mass (gas, dust and stars) of a large spiral galaxy. This gas mass is consistent with the dynamical mass of the galaxy inferred from the CO emission line-width. The CO line luminosity is twenty times larger than is seen in nearby (z < 0.3) ultra-luminous (L>3xl011 M⊙) galaxies3–5. Although it is extremely gas-rich, with a higher CO luminosity than any other galaxy, the infrared to CO luminosity ratio of 10214 + 4724 is twice that of most infrared-luminous galaxies, and ∼30 times higher than that of normal spirals. Its infrared colours and high infrared/CO luminosity ratio indicate that 10214 + 4724 is similar to nearby ultra-luminous galaxies5 that are known to be merging. This galaxy is a primaeval molecular galaxy with the mass of a large spiral, but with most of the mass in molecular gas rather than stars.
Access optionsAccess options
Subscribe to Journal
Get full journal access for 1 year
only $3.90 per issue
All prices are NET prices.
VAT will be added later in the checkout.
Rent or Buy article
Get time limited or full article access on ReadCube.
All prices are NET prices.
Rowan-Robinson, M. et al. Nature 351, 719–721 (1991).
Brown, R. L. & Vanden Bout, P. A. Astr. J. 102, 1956–1959 (1991).
Downes, D., Solomon, P. M. & Radford, S. J. E. in Dynamics of Galaxies and their Molecular Cloud Distributions (eds Combes, F. & Casoli, F.) 295–298 (Kluwer, Dordrecht, 1991).
Radford, S. J. E., Solomon, P. M. & Downes, D. Astrophys. J. 369, L15–L18 (1991).
Sanders, D. B., Soifer, B. T., Elias, J. H., Neugebauer, G. & Matthews, K. Astrophys. J. 328, L35–L39 (1988).
Weinberg, S. Gravitation and Cosmology (Wiley, New York, 1972).
Solomon, P. M. & Sage, L. J. Astrophys. J. 334, 613–625 (1988).
Solomon, P. M., Radford, S. J. E. & Downes, D. Astrophys. J. 348, L53–L56 (1990).
Solomon, P. M., Rivolo, A. R., Barrett, J. & Yahil, A. Astrophys. J. 319, 730–741 (1987).
Scoville, N. Z. et al. Astrophys. J. Suppl. 63, 821–915 (1987).
Scoville, N. Z., Sargent, A. I., Sanders, D. B. & Soifer, B. T. Astrophys. J. 366, L5–L9 (1991).
Young, J. et al. Astrophys. J. 304, 443–458 (1986).
Sanders, D. B. in Dynamics of Galaxies and their Molecular Cloud Distributions (eds Combes, F. & Casoli, F.) 417–423 (Kluwer, Dordrecht, 1991).
Sanders, D. B. et al. Astr. Astrophys. 213, L5–L8 (1989).
Kleinmann, S. G. et al. Astrophys. J. 328, 161–169 (1988).
Solomon, P. M., Downes, D. & Radford, S. J. E. Astrophys. J. 387, L55–L61 (1992).
Scoville, N. Z. & Young, J. S. Astrophys. J. 265, 148–165 (1983).
About this article
Monthly Notices of the Royal Astronomical Society (2018)
The MALATANG Survey: The L GAS–L IR Correlation on Sub-kiloparsec Scale in Six Nearby Star-forming Galaxies as Traced by HCN J = 4 → 3 and HCO+ J = 4 → 3
The Astrophysical Journal (2018)
Monthly Notices of the Royal Astronomical Society (2017)
EXCITATION MECHANISMS FOR HCN(1–0) AND HCO+(1–0) IN GALAXIES FROM THE GREAT OBSERVATORIES ALL-SKY LIRG SURVEY
The Astrophysical Journal (2015)
Monthly Notices of the Royal Astronomical Society (2014)