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

S. J. Curran·M. T. Murphy·J. K. Webb·F. Rantakyro·L. E. B. Johansson·S. Nikolic
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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.

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S. J. Curran, M. T. Murphy, J. K. Webb, F. Rantakyro, L. E. B. Johansson, S. Nikolic. 2002-09-10. A search for molecules in damped Lyman-alpha absorbers occulting millimetre-loud quasars. https://doi.org/10.1051/0004-6361%3A20021231

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