2013/07/01 by C. D. Dermer, Dermer, C. D., A. W. Strong +4
Physics and Astronomy · #Astrophysics and Cosmic Phenomena #Dark Matter and Cosmic Phenomena #FOS: Physical sciences #High Energy Astrophysical Phenomena (astro-ph.HE) #Particle Detector Development and Performance
paper · pdf · doi:10.48550/arxiv.1307.0497
openalex publication_date 2013/07/01 · openalex created_date 2025/10/10 · openalex updated_date 2026/07/28
More than 90% of the Galactic gas-related gamma-ray emissivity above 1 GeV is attributed to the decay of neutral pions formed in collisions between cosmic rays and interstellar matter, with lepton-induced processes becoming increasingly important below 1 GeV. Given the high-quality measurements of the gamma-ray emissivity of local interstellar gas between ~50 MeV and ~4 GeV obtained with the Large Area Telescope on board the Fermi space observatory, it is timely to re-investigate this topic in detail, including the hadronic production mechanisms. The emissivity spectrum will allow the interstellar cosmic-ray spectrum to be determined reliably, providing a reference for origin and propagation studies as well as input to solar modulation models. A method for such an analysis and illustrative results are presented.