{"about":{"site":"https://codewithpapers.app","non_affiliation":"Code with Papers and Syntology are not affiliated with, endorsed by, or sponsored by Papers with Code, Meta, or the pwc-archive mirror.","licence":"CC BY-SA 4.0","licence_url":"https://creativecommons.org/licenses/by-sa/4.0/legalcode","attribution":"https://codewithpapers.app/attribution","modified":"archive material modified by Syntology; see the attribution page"},"url":"/paper/angular-distribution-of-gamma-rays-produced","title":"Angular Distribution of Gamma Rays Produced in Proton-Proton Collisions","arxiv_id":"2412.08726","date":"2024-12-11","proceeding":null,"authors":["Spencer Griffith","John F. Beacom","Jung-Tsung Li","Annika H. G. Peter"],"abstract":"Accurate modeling of how high-energy proton-proton collisions produce gamma rays through the decays of pions and other secondaries is needed to correctly interpret astrophysical observations with the Fermi-LAT telescope. In the existing literature on cosmic-ray collisions with gas, the focus is on the gamma-ray yield spectrum, $d N_\\gamma/dE$. However, in some situations, the joint energy and angular distribution can be observed, so one needs instead $d^2 N_\\gamma/dE \\, d\\Omega$. We provide calculations of this distribution over the energy range from the pion production threshold to $100~{\\rm GeV}$, basing our results on FLUKA simulations. We provide the results in tabular form and provide a Python tool on GitHub to aid in utilization. We also provide an approximate analytic formula that illuminates the underlying physics. We discuss simplified examples where this angular dependence can be observed to illustrate the necessity of taking the joint distribution into account.","url_abs":"https://arxiv.org/abs/2412.08726v1","url_pdf":"https://arxiv.org/pdf/2412.08726v1.pdf","source":{"archive":"pwc-archive (Hugging Face), CC BY-SA 4.0","snapshot":"2025-07-28","licence_url":"https://creativecommons.org/licenses/by-sa/4.0/legalcode","row_kind":"links_only","authors_date_abstract":"arXiv metadata, CC0 1.0 (https://info.arxiv.org/help/license), from the Kaggle arXiv metadata snapshot of 2026-09-12"},"code_links":[{"paper_slug":"angular-distribution-of-gamma-rays-produced","repo_url":"https://github.com/skgriffith/Gamma-Ray-Angular-Distribution","is_official":1,"mentioned_in_paper":0,"mentioned_in_github":0,"framework":"none","reach":null}],"tasks":[],"methods":[],"datasets_introduced":[],"methods_introduced":[],"results":[],"syntology":{"atlas_url":null,"mcp":null,"developers":"https://syntology.ai/developers"},"arxiv_metadata":null,"syntology_extracted_results":null}