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Detection of CO (2-1) and Radio Continuum Emission from the z = 4.4 QSO BRI 1335–0417
Astrophysical Journal Letters (1999)
  • C L Carilli
  • Karl M Menten
  • Min S. Yun, University of Massachusetts - Amherst
We have detected redshifted CO (2-1) emission at 43 GHz and radio continuum emission at 1.47 and 4.86 GHz from the z = 4.4 QSO BRI 1335-0417 using the Very Large Array. The CO data imply optically thick emission from warm (>30 K) molecular gas with a total mass, M(H2), of (1.5 ± 0.3) × 1011 Msun, using the standard Galactic gas mass-to-CO luminosity conversion factor. We set an upper limit to the CO source size of 1farcs1 and a lower limit of 0farcs23(Tex/50 K)-1/2, where Tex is the gas excitation temperature. We derive an upper limit to the dynamical mass of 2 × 1010sin−2 i Msun, where i is the disk inclination angle. Reconciling the gas mass with the dynamical mass requires either a nearly face-on disk (i < 25°) or a gas mass-to-CO luminosity conversion factor significantly lower than the Galactic value. The spectral energy distribution from the radio to the rest-frame infrared of BRI 1335-0417 is consistent with that expected from a nuclear starburst galaxy, with an implied massive star formation rate of 2300 ± 600 Msun yr-1.
  • galaxies: distances and redshifts,
  • galaxies: evolution,
  • galaxies: starburst,
  • infrared: galaxies,
  • radio continuum: galaxies,
  • radio lines: galaxies
Publication Date
August 10, 1999
Publisher Statement
Citation Information
C L Carilli, Karl M Menten and Min S. Yun. "Detection of CO (2-1) and Radio Continuum Emission from the z = 4.4 QSO BRI 1335–0417" Astrophysical Journal Letters Vol. 521 Iss. 1 (1999)
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