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A Molecular Gas of z<0.2 Infrared-Excess, Optical QSOs

A. S. Evans·D. T. Frayer·J. A. Surace·D. B. Sanders
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Abstract

Millimeter-wave (CO) observations of optically-selected QSOs are potentially a powerful tool for studying the properties of both the QSOs and their host galaxies. We summarize here a recent molecular gas survey of z<0.17 optical QSOs with infrared (IR) excess, L_IR (8-1000 um) / L_bbb (0.1-1.0 um) > 0.36. Eight of these QSOs have been detected to date in CO(1-0), and the derived molecular gas masses are in the range 1.7-35x10^9 M_sun. The high L_IR / L'_CO of QSOs relative to the bulk of the local (z<0.2) IR luminous galaxy merger population is indicative of significant heating of dust (L_IR) by the QSO nucleus and/or by massive stars created in the host galaxy with high efficiency (i.e., per unit molecular gas, L'_CO).

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A. S. Evans, D. T. Frayer, J. A. Surace, D. B. Sanders. 2001-03-13. A Molecular Gas of z<0.2 Infrared-Excess, Optical QSOs. https://arxiv.org/abs/astro-ph/0103197

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