Cosmic-ray ionization and heating in molecular clouds

Mon, Oct 26, 2015 at 3:00 pm

131A Campbell Hall

Daniele Galli (INAF)


Low-energy cosmic rays are an important source of ionization for the interstellar medium, influencing its chemical, thermal and dynamical evolution. Available observational determinations of the cosmic-ray ionization rate in diffuse clouds and recent data from the Voyager I spacecraft support the existence of a significant flux of cosmic-ray nuclei and electrons below ~100 MeV. However, the penetration of this low-energy component inside dense clouds or circumstellar disks is hampered by strong losses and magnetic effects. In this talk I will review recent theoretical advances on this subject and discuss their consequences on the process of disk formation in collapsing magnetized clouds.