1111.6936 (Nick Indriolo et al.)

Investigating the Cosmic-Ray Ionization Rate in the Galactic Diffuse Interstellar Medium through Observations of H3+    [PDF]

Nick Indriolo, Benjamin J. McCall

Observations of H3+ in the Galactic diffuse interstellar medium (ISM) have led to various surprising results, including the conclusion that the cosmic-ray ionization rate (zeta_2) is about 1 order of magnitude larger than previously thought. The present survey expands the sample of diffuse cloud sight lines with H3+ observations to 50, with detections in 21 of those. Ionization rates inferred from these observations are in the range (1.7+-1.3)x10^-16 s^-1View original: http://arxiv.org/abs/1111.6936