Relativistic calculations of neutron and gamma-ray spectra from beam–target reactions in magnetized plasmas

We present a fully relativistic analytical model for calculating synthetic spectra from beam–target fusion reactions. When the target particle is assumed at rest, Monte Carlo sampling of reactant velocities can be avoided, and spectrum computations are considerably faster. A fully analytical treatment additionally gives more insight into the spectrum formation. The fully relativistic formulation now makes it possible to handle massless particles in the model, for example from one-step gamma-ray reactions, and the results are corroborated by simulations from established codes.