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Imaging low order CO emission from the z=4.12 QSO PSS 2322+1944

C. Carilli·P. Cox·F. Bertoldi·K. M. Menten·A. Omont
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Abstract

We present observations of CO 1-0 and CO 2-1 emission from the z = 4.12 QSO PSS 2322+1944 using the Very Large Array. The CO emission is extended on a spatial scale of 2''. This extension could reflect the double nature of the QSO as seen in the optical, or could be diffuse emission with a (redshift corrected) mean brightness temperature of 2.8 K for the CO 2-1 line. We find the CO excitation conditions are lower than in two other IR-luminous z > 4 QSOs, suggesting the presence of a significant contribution from cooler, lower density molecular gas (n(H_2) = 5x10^3 /cm^3), although such a conclusion is complicated by the possibility of differential gravitational magnification.

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C. Carilli, P. Cox, F. Bertoldi, K. M. Menten, A. Omont. 2002-04-15. Imaging low order CO emission from the z=4.12 QSO PSS 2322+1944. https://doi.org/10.1086/341269

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