IRAM observations of JVAS/CLASS gravitational lenses

E. Xanthopoulos; F. Combes; T. Wiklind

doi:10.1046/j.1365-8711.2001.04414.x

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arXiv · astro-ph/0010454

IRAM observations of JVAS/CLASS gravitational lenses

E. Xanthopoulos·F. Combes·T. Wiklind

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Abstract

We have searched for molecular absorption lines at millimeter wavelengths in eleven gravitational lens systems discovered in the JVAS/CLASS surveys of flat spectrum radio sources. Spectra of only one source 1030+074 were obtained in the 3-, 2- and 1.3-millimeter band at the frequencies corresponding to common molecular transitions of CO and HCO+ as continuum emission was not found in any of the other sources. We calculated upper limits to the column density in molecular absorption for 1030+074, using an excitation temperature of 15 K, to be N_{CO} < 6.3 x 10^{13} cm^{-2} and N_{HCO+} < 1.3 x 10^{11} cm^{-2}, equivalent to hydrogen column density of the order N_H < 10^{18} cm^{-2}, assuming standard molecular abundances. We also present the best upper limits of the continuum at the lower frequency for the other 10 gravitational lenses.

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E. Xanthopoulos, F. Combes, T. Wiklind. 2000-10-23. IRAM observations of JVAS/CLASS gravitational lenses. https://doi.org/10.1046/j.1365-8711.2001.04414.x

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