A search for molecules in damped Lyman-alpha absorbers occulting millimetre-loud quasars

Abstract

We have used the SEST 15-metre and Onsala 20-metre telescopes to perform deep (r.m.s. >~ 30 mJy) integrations of various molecular rotational transitions towards damped Lyman-alpha absorption systems (DLAs) known to occult millimetre-loud quasars. We have observed 6 new systems and improved the existing limits for 11 transitions. These limits may be approaching the sensitivities required to detect new systems and we present a small number of candidate systems which we believe warrant further observation.

7 pages, 1 PS figure, 4 tables. Accepted by A&A

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Cited by in corpus (6)

• Further evidence for a variable fine-structure constant from Keck/HIRES QSO absorption spectra
• Inspiraling Halo Accretion Mapped in Lyman-$\alpha$ Emission around a $z\sim 3$ Quasar
• Spin temperatures and covering factors for HI 21-cm absorption in damped Lyman-alpha systems
• Molecular fraction limits in damped Lyman-alpha absorption systems
• A search for high redshift molecular absorption lines toward millimetre-loud, optically faint quasars
• A 22GHz search for molecular absorption at z~3 with the upgraded ATCA