Detection of D2H+ in the Dense Interstellar Medium

C. Vastel; T. G. Phillips; H. Yoshida

doi:10.1086/421265

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arXiv · astro-ph/0403537

Detection of D2H+ in the Dense Interstellar Medium

C. Vastel·T. G. Phillips·H. Yoshida

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Abstract

The 692 GHz para ground-state line of D2H+ has been detected at the Caltech Submillimeter Observatory towards the pre-stellar core 16293E. The derived D2H+ abundance is comparable to that of H2D+, as determined by observations of the 372 GHz line of ortho-H2D+. This is an observational verification of recent theoretical predictions (Roberts, Herbst & Millar 2003), developed to explain the large deuteration ratios observed in cold, high-density regions of the interstellar medium associated with low mass pre-stellar cores and protostars. This detection confirms expectations that the multiply deuterated forms of H3+ were missing factors of earlier models. The inclusion of D2H+ and D3+ in the models leads to predictions of higher values of the D/H ratio in the gas phase.

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C. Vastel, T. G. Phillips, H. Yoshida. 2004-04-07. Detection of D2H+ in the Dense Interstellar Medium. https://doi.org/10.1086/421265

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