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arXiv · 0805.4297

Tentative detection of phosphine in IRC+10216

Abstract

The J,K = 1,0-0,0 rotational transition of phosphine (PH3) at 267 GHz has been tentatively identified with a T_MB = 40 mK spectral line observed with the IRAM 30-m telescope in the C-star envelope IRC+10216. A radiative transfer model has been used to fit the observed line profile. The derived PH3 abundance relative to H2 is 6 x 10^(-9), although it may have a large uncertainty due to the lack of knowledge about the spatial distribution of this species. If our identification is correct, it implies that PH3 has a similar abundance to that reported for HCP in this source, and that these two molecules (HCP and PH3) together take up about 5 % of phosphorus in IRC+10216. The abundance of PH3, as that of other hydrides in this source, is not well explained by conventional gas phase LTE and non-LTE chemical models, and may imply formation on grain surfaces.

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M. Agúndez, J. Cernicharo, J. R. Pardo, M. Guélin, T. G. Phillips. 2008-05-28. Tentative detection of phosphine in IRC+10216. https://doi.org/10.1051/0004-6361%3A200810193

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