3-01
Peter Schilke
Universität zu Köln
Characterizing the interstellar medium with Hydrides
Interstellar hydrides (i.e. molecules containing a single heavy element atom with one or more hydrogen atoms) are the building blocks of interstellar chemistry. Their simplicity ensures that they exist in a variety of environments which are hostile to the formation of more complex molecules, e.g. in diffuse gas making the transition from atomic to molecular. They consequently can be used to characterize their environmental conditions, e.g. the fraction of molecular relative to atomic gas, the cosmic ray flux etc. Due to their low moment of inertia, the frequencies tend to be in the THz range, and they were largely unstudied before Herschel. The SOFIA legacy project HyGAL has been designed to explore the detection space opened, but only cursorily explored by Herschel. I will describe the survey strategy, and show first results from SOFIA and ancillary data we have obtained.