A Line Survey of Orion KL from 325 to 360 GHz
Astrophysical Journal Supplement Series
We present a high-sensitivity spectral line survey of the high-mass star-forming region Orion KL in the 325È360 GHz frequency band. The survey was conducted at the Caltech Submillimeter Observatory on Mauna Kea, Hawaii. The sensitivity achieved is typically 0.1È0.5 K and is limited mostly by the sideband separation method utilized. We Ðnd 717 resolvable features consisting of 1004 lines, among which 60 are unidentiÐed. The identiÐed lines are due to 34 species and various isotopomers. Most of
... topomers. Most of the unidentiÐed lines are weak, and many of them most likely due to isotopomers or vibrationally or torsionally excited states of known species with unknown line frequencies, but a few reach the 2È5 K level. No new species have been identiÐed, but we were able to strengthen evidence for the identiÐcation of ethanol in Orion and found the Ðrst nitrogen sulÐde line in this source. The molecule dominating the integrated line emission is which emits twice the intensity of CO, followed by SO, which is only SO 2 , slightly stronger than CO.