2003A&A...407..589W

The results of a submillimetre wavelength spectral line survey between 455.1-507.4GHz of the Orion-KL hot cloud core are reported. A total of 254 lines were detected to a main beam brightness temperature sensitivity T_mb∼1-3K. The detected lines are identified as being associated with 30 different molecular species or their isotopomeric variants. The strongest line detected was the J=4-3 transition of the CO molecule. Apart from abundant diatomic rotors such as CO and CS, the spectrum is dominated by SO, SO₂ and CH₃OH and large organic molecules such as (CH₃)₂O, CH₃CN, C₂H₃CN, C₂H₅CN and HCOOCH₃ which make up ∼72% of the total number of lines; unidentified lines ∼13%; and other lines the remaining ∼15% of the total. Rotational temperatures and column densities derived using standard rotation diagram analysis techniques were found to range from 70-300K, and 10¹⁴-10¹⁷cm² respectively.