Cosmic Rays in the Interstellar Medium

摘要

In this article we will highlight the importance of cosmic rays for the chemistry of the interstellar medium (ISM) in our own Milky Way as well as in external galaxies. We will review the methodologies employed to determine the cosmic ray ionization rates in the ISM, how cosmic rays rales can influence the determination of the mass of a galaxy and, finally, how cosmic rays affect star formation and its rate.