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Plateau de Bure observations of mm-wave molecular absorption from CO , HCO , and HCN

R. Lucas, H. Liszt
Institut de Radioastronomie Millimétrique, 300 Rue de la Piscine, F-38406 Saint Martin d'Hères, France
National Radio Astronomy Observatory, 520 Edgemont Road, Charlottesville, VA, USA 22903-2475
Abstract: We used the Plateau de Bure Interferometer to synthesize 3mm absorption line profiles of CO , HCO , and HCN in local gas seen toward the extragalactic continuum sources 0212+735, 0355+508 (NRAO150), and 2200+420 (BL Lac ). The HCO and HCN profiles are remarkable in having more and wider lines than CO seen in emission and absorption (Figs. 3 and 4). The relative molecular abundances vary widely. For 11 velocity components we find <N(HCO ); <N(CO )/N(HCO ), ranging from 50 to 1400; <N(CO )/N(HCN), ranging from 50 to 300; <N(HCN)/N(HCO ), ranging from 0.28 to 4.7.

Figure: Emission and absorption profiles toward 0212+735 (see Section 2). The channel spacing is 0.26 kms ; the resolution of the absorption profiles is 0.47 kms

Figure: Profiles toward 0355+508, as in Figure 3.

Robert Lucas
Thu Mar 9 14:51:14 MET 1995