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The Sub-millimeter Rotational Spectrum of Ethylene Glycol up to 890 GHz and Application to ALMA Band 10 Spectral Line Data of NGC 6334I

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 نشر من قبل Brett McGuire
 تاريخ النشر 2019
  مجال البحث فيزياء
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The rotational spectrum of the most stable conformer of ethylene glycol (HO(CH$_2$)$_2$OH) has been recorded between 360-890 GHz using a frequency-modulation sub-millimeter spectrometer. The refinement and extension of the spectroscopic parameters over previous efforts provides predicted catalog frequencies for ethylene glycol with sufficient accuracy for comparison to high-frequency astronomical data. The improvement in the cataloged line positions, and the need for improved accuracy enabled by high-frequency laboratory work, is demonstrated by an analysis of ethylene glycol emission at 890 GHz in the high-mass star-forming region NGC 6334I in ALMA Band 10 observations. The need for accurate rotational spectra at sub-millimeter wavelengths/THz frequencies is discussed.

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