CH in translucent molecular clouds

  • Loris Magnani
5. Masers in Star-Forming Regions (General)
Part of the Lecture Notes in Physics book series (LNP, volume 412)


Under typical interstellar cloud conditions, the ground state hyperfine transitions of the methylidyne radical (CH) are anomalously excited. The resulting weak maser emission is particularly succesful in tracing low-density molecular gas. The CH ground state transitions at 3.3 GHz are routinely detected in diffuse clouds, translucent clouds, and dark molecular clouds. Recent observations of CH emission in translucent clouds are reviewed and a value for the N(H2)W(CO) conversion factor appropriate for the translucent cloud MBM16 is derived on the basis of CO and CH data.


Conversion Factor Molecular Cloud Column Density Interstellar Cloud Visual Extinction 
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Copyright information

© Springer-Verlag 1993

Authors and Affiliations

  • Loris Magnani
    • 1
  1. 1.Department of Physics and AstronomyUniversity of GeorgiaAthens

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