2001/06/29 by G. T. Birk, A. R. Crusius--Waetzel, A. Crusius-Wätzel +1 · 4 citations
Engineering · Physics and Astronomy · #Astrophysics and Cosmic Phenomena #Particle Accelerators and Free-Electron Lasers #Particle accelerators and beam dynamics #astro-ph
paper · pdf · doi:10.1086/322394
14 pages, 2 figures, acc. for publ. in ApJ
arxiv created 2001/06/29 · openalex publication_date 2001/09/20 · arxiv updated 2009/12/01 · openalex created_date 2025/10/10 · openalex updated_date 2026/07/31
Extremely flat and inverted radio spectra as observed in galactic nuclei and BL Lac sources are still a challenge for fast-particle acceleration models. Continuous acceleration by electric fields in reconnection regions can result in almost-constant particle distributions and therefore in inverted synchrotron spectra independent of the details of the injected spectra. These spectra are calculated from a spatially averaged diffusion transport equation in momentum space that includes systematic momentum gains and losses as well as finite particle-escape lifetimes.