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Dense molecular gas in quasar host galaxies: a search for HCN emission from BR B1202-0725 at z=4.695

Kate G. Isaak·Claire J. Chandler·Christopher L. Carilli
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Abstract

We report on the results of a search using the VLA for redshifted HCN(1-0) emission from the host galaxy of BR B1202-0725, an optically luminous quasar at z=4.695. The host galaxy emits strongly in the rest-frame far-infrared, and shows characteristics very similar to that of more local, ultraluminous infrared galaxies, in which a significant fraction of the far-infrared emission is powered by star formation. We find a 3-sigma upper limit to the HCN(1-0) emission of 4.9 x 10^10 K kms^-1 pc^2, assuming a lambda-cosmology. This limit is consistent with correlations derived from measurements of the HCN, CO, and far-infrared emission for a sample of more local galaxies, including starbursts (Solomon et al, 1992a).

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Kate G. Isaak, Claire J. Chandler, Christopher L. Carilli. 2003-12-04. Dense molecular gas in quasar host galaxies: a search for HCN emission from BR B1202-0725 at z=4.695. https://doi.org/10.1111/j.1365-2966.2004.07419.x

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