8-12 juin, 2014


Molecular Tracers of Low Velocity Shocks in Molecular Clouds

Andy Pon (University of Leeds; MPE)

Doug Johnstone (NRC-HIA; Joint Astronomy Center; University of Victoria), Michael Kaufman (San Jose State University; NASA Ames), Paola Caselli (MPE) and Jonathan C. Tan (University of Florida)

Molecular clouds contain supersonic turbulence, which should decay on the order of a crossing time. We have run numerical models for the type of shock expected to be generated by turbulence in molecular clouds and, by estimating the typical turbulent energy dissipation rate, we have predicted the shock emission expected to come from a molecular cloud. We find that CO is the primary coolant in these low velocity shocks and we predict that mid-J CO lines (J = 6 to 5 and higher) should trace the shocked gas in a molecular cloud. We present Herschel observations of mid-J CO lines towards both a low mass star forming region and four quiescent cores embedded in IRDCs and show that there must be a hot gas component within some of these regions.

Mode de présentation: 2014-06-09 10:45 (doit être confirmé par le SOC)