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Production of 12.2 GHz CH3OH masers — Preliminary results of an excitation study

  • R. Peng
  • J. B. Whiteoak
8. Methanol Masers in Star Forming Regions
Part of the Lecture Notes in Physics book series (LNP, volume 412)

Abstract

Excitation of the 20 → 3−1 E transition of CH3OH at 12.2 GHz has been examined in a statistical equilibrium study. The results show that mase emission can be produced in a molecular cloud with a bright HII region as immediate background. For cloud of kinetic temperature of 30 K, velocity gradient of 5 km 8−1 pc−1, H2 density of ≈ 105 cm−3 and methanol abundance of 10−6, and a continuum background of 50 K, the maser emission can reach a brightness temperature of ≈ 1300 K. This value would be much higher with smaller velocity gradient, where bright maser emission is usually expected.

Keywords

Velocity Gradient Brightness Temperature Molecular Cloud Kinetic Temperature Maser Emission 
These keywords were added by machine and not by the authors. This process is experimental and the keywords may be updated as the learning algorithm improves.

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Copyright information

© Springer-Verlag 1993

Authors and Affiliations

  • R. Peng
    • 1
  • J. B. Whiteoak
    • 2
  1. 1.Department of AstronomyUniversity of Illinois at Urbana-ChampaignUrbanaUSA
  2. 2.CSIRO Australia Telescope National FacilityEppingAustralia

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