Detection of the 23–22 emission line of sulphur monoxide and its relevance to magnetic fields in Orion

Ronald Brown, Peter Godfrey, David Winkler

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We have observed the 23–22 transition of SO at 36 201.942 MHz in Orion A with ∆Ta = 0.4 K and ∆v = 23 km/s. From an analysis of the Zeeman effect on this line we deduce that, contrary to the proposal of Clark & Johnson that a magnetic field of 6 gauss is broadening the observed SO lines, the field cannot be greater than 1 gauss. Other considerations make it more plausible that the observed line broadenings are attributable to kinematic effects of expanding or collapsing gas shells and that the magnetic field in the Orion molecular cloud is considerably weaker than 1 gauss.
Original languageEnglish
Pages (from-to)1-6
Number of pages6
JournalMonthly Notices of the Royal Astronomical Society
Issue number1
Publication statusPublished - 1980

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