The Amount of CH Produced during CH⁺ Synthesis in Interstellar Clouds

Abstract

A particularly useful constraint for models of CH⁺ formation in interstellar clouds is knowledge of the amount of CH associated with CH⁺ synthesis. For lines of sight with no detectable CN absorption, this column of CH can be inferred through a combined analysis of C I excitation and simplified chemical models. The approach is applied to data for two lines of sight, those toward 23 Ori and β¹ Sco, for which N(CH)/N(CH⁺) <= 0.40.

Based on observations obtained with the NASA/ESA Hubble Space Telescope through the Space Telescope Science Institute, which is operated by the Association of Universities for Research in Astronomy, Inc., under NASA contract NAS 5-26555.