Cosmic rays, radio and gamma-ray emission from the remnant of supernova 1987A

The acceleration of cosmic rays (CRs) in the supernova remnant (SNR) 1987A is investigated. A self-consistent theoretical description is based on the diffusion CR transport equation together with gas-dynamical equations for the medium (gas). The model consistently allows for the actual geometry of the expanding shock and for the inverse effect of accelerated CRs on its structure and dynamics. It also assumes that a 10−2 fraction of the gas particles are injected into the acceleration at the shock front. Parameters of the ambient medium—the SN 1987A progenitor wind—were chosen in such a way as to reproduce the observed expansion law of SNR 1987A. A single set of physical parameters is shown to ensure reasonable agreement between the calculated radio spectrum for SNR 1987A and available experiments. The expected spectrum of gamma rays from the decay of π0 mesons produced when the CR nucleon component collides with ambient atoms is calculated. The integrated gamma-ray spectrum at energies ∈γ≲1 TeV is hard, Fγ∝∈γ−0.6; the expected total flux Fγ(1 TeV) at the current epoch is 7×10−13 cm−2 s−1, and its two-fold rise is expected by 2006.