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Previously unobserved water lines detected in the post-impact spectrum of Comet Tempel 1

R. J. Barber·S. Miller·T. S. Stallard·J. Tennyson
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Abstract

The recently puplished Barber-Tennyson (BT2) synthetic H$_2$O water line list is the most complete and accurate line list in existence. It is finding application in a wide range of astrophysical environments. UKIRT spectra of comet Tempel 1, obtained after the 'Deep Impact' event, revealed several known H$_2$O solar pumped fluorescent (SPF)lines in the 2.8945 to 2.8985 $μ$m region. In addition, using synthetic spectra produced with BT2, several emission lines were identified that had not previously been recorded in cometary spectra. Unlike the SPF lines, which are transitions from doubly-excited stretch states, these transitions, that we label 'SH', are from states with three or four quanta of vibrational excitation. The SH features were particularly strong during the period 20-40 minutes after impact.

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R. J. Barber, S. Miller, T. S. Stallard, J. Tennyson. 2006-10-23. Previously unobserved water lines detected in the post-impact spectrum of Comet Tempel 1. https://arxiv.org/abs/astro-ph/0610673

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