Non-equilibrium excitation of methanol in Galactic molecular clouds: multi-transitional observations at 2 mm

Details Non-equilibrium excitation of methanol in Galactic molecular clouds: multi-transitional observations at 2 mm Non-equilibrium excitation of methanol in Galactic molecular clouds: multi-transitional observations at 2 mm

1999-06-04

arxiv.org/abs/astro-ph/9906090v1

Astrophys.J.Suppl. 123 (1999) 515-536

Astronomy and Astrophysics

Astrophysics

23 pages paper (uses aasms4.sty), 12 pages tables (uses apjpt4.sty), 10 Jpeg figures, submitted to the ApJS

Scientific paper

10.1086/313240

We observed 14 methanol transitions near lambda=2 mm in Galactic star-forming regions. Broad, quasi-thermal J(0)-J(-1)E methanol lines near 157 GHz were detected toward 73 sources. Together with the 6(-1)-5(0)E and 5(-2)-6(-1)E lines at 133 GHz and the 7(1)-7(0)E line at 165 GHz, they were used to study the methanol excitation. In the majority of the observed objects, the Class I 6(-1)-5(0)E transition is inverted, and the Class II 5(-2)-6(-1)E and 6(0)-6(-1)E transitions are overcooled. This is exactly as predicted by models of low gain Class I masers. The absence of the inversion of Class II transitions 5(-2)-6(-1)E and 6(0)-6(-1)E means that quasi-thermal methanol emission in all objects arises in areas without a strong radiation field, which is required for the inversion.

Affiliated with

Also associated with

No associations

Rating

Non-equilibrium excitation of methanol in Galactic molecular clouds: multi-transitional observations at 2 mm does not yet have a rating. At this time, there are no reviews or comments for this scientific paper.

If you have personal experience with Non-equilibrium excitation of methanol in Galactic molecular clouds: multi-transitional observations at 2 mm, we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and Non-equilibrium excitation of methanol in Galactic molecular clouds: multi-transitional observations at 2 mm will most certainly appreciate the feedback.

Rate now

Comments { 0 }

Profile ID: LFWR-SCP-O-126669