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Search for Lambda-Doubling Transitions of SiH in Orion KL

Vincent L. Fish
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Abstract

A recent submillimeter line survey of Orion KL claimed detection of SiH. This paper reports on GBT observations of the 5.7 GHz Lambda-doubling transitions of SiH in Orion. Many recombination lines, including C164-delta, are seen, but SiH is not detected. The nondetection corresponds to an upper limit of 1.5 x 10^15 cm^-2 (4 sigma) for the beam-averaged column density of SiH. This suggests that the fractional abundance of SiH in the extended ridge is no more than twice that in the hot core.

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Vincent L. Fish. 2006-06-20. Search for Lambda-Doubling Transitions of SiH in Orion KL. https://doi.org/10.1086/507026

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