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Search for radio recombination lines towards the gravitational lens PKS 1830-211

Niruj R. Mohan·K. R. Anantharamaiah·W. M. Goss
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Abstract

A search for radio recombination lines near 20 cm at z=0.193 and z=0.886 towards the gravitational lens system PKS 1830-211 has yielded upper limits on the line optical depth of 5 x 10^{-5} and 5 x10^{-4} at the two redshifts respectively. Based on the non-detections, we derive upper limits to the emission measure of the ionized gas in the absorbing systems. We also present continuum flux density measurements over the frequency range 0.3-45 GHz made at a single epoch.

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Niruj R. Mohan, K. R. Anantharamaiah, W. M. Goss. 2000-04-21. Search for radio recombination lines towards the gravitational lens PKS 1830-211. https://arxiv.org/abs/astro-ph/0004307

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