On the origin of cosmic rays: Some problems in highenergy astrophysics

This paper reviews the present state of the problem of the origin of cosmic rays. Primary attention is paid to galactic diffusion models with a halo, and questions of cosmic-ray chemical composition, electron component, and synchrotron galactic radioemission. The author's conclusion is that models with a large halo with a characteristic cosmic-ray age $T_{cr}\sim10^8$ years are confirmed by radio data, and at least do not contradict the information on cosmic-ray chemical composition. The paper also deals with the problems of anisotropy, plasma phenomena in cosmic rays, and the prospects of gamma-ray astronomy.