1999/03/23 by E. Parizot, Etienne Parizot, Parizot, Etienne +1
Physics and Astronomy · #Gamma-ray bursts and supernovae #Neutrino Physics Research #Nuclear physics research studies #astro-ph
paper · pdf · doi:10.48550/arxiv.astro-ph/9903356
9 pages, 1 figure, accepted for publication in A&A
arxiv created 1999/03/23 · arxiv updated 2009/12/01
We present a general model allowing one to calculate the distribution function of energetic particles in the interstellar medium, and hence any relevant nuclear reaction rate, for any given time-dependent injection function, as well as in situations when the propagation coefficients themselves are non stationary. We review and provide physical interpretation of general formal solutions of a propagation equation taking into account energy losses, nuclear destruction and escape. Both one-zone and extended models are investigated. Our main goal is to provide standard and general tools for subsequent use in nuclear astrophysics, notably to calculate the gamma-ray emission and spallation rates associated with energetic events and specific acceleration mechanisms. Considering the stationary limit of the model, we show that only time-dependent calculations can probe the density dependence of the physical processes under study, while steady-state models can in principle only give information about density-independent processes.