Molecular oxygen abundance is a key parameter in understanding the chemical network of the interstellar *** estimate the molecular oxygen column density and abundance for a sample of Galactic massive star formation re...
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Molecular oxygen abundance is a key parameter in understanding the chemical network of the interstellar *** estimate the molecular oxygen column density and abundance for a sample of Galactic massive star formation regions based on observations from the Submillimiter Wave Astronomy Satellite (SWAS) *** obtained an averaged O2spectrum based on this sample using the (SWAS) survey data (O2,487.249 GHz,N=3–1,J=3–2).No emission or absorption feature is seen around the supposed central velocity with a total integration time of ttotal=8.67×10~3hr and an rms noise per channel of 1.45 m *** a kinetic temperature Tkin=30 K,we derive the 3σupper limit of the O2column density to be 3.3×1015cm-2,close to the lowest values reported in Galactic massive star formation regions in previous *** corresponding O2abundance upper limit is6.7×10-8,lower than all previous results based on SWAS observations and is close to the lowest reported value in massive star formation *** a galactic scale,our statistical results confirm a generally low O2abundance for Galactic massive star formation *** abundance is also lower than results reported in extragalactic sources.
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