Origin and propagation of cosmic rays in the range 100-1000 GeV

Abstract

Recent results have indicated that there is a significant anisotropy in the arrival directions of cosmic ray particles having median energy in the range 200-300 GeV. The assumption is made that the majority of these particles are of Galactic origin and conclusions are drawn about their propagation in the local region of the Galaxy. Observations on cosmic gamma rays indicate that there is either a long-term gradient of cosmic ray intensity along the local spiral arm or that the Vela supernova is producing a temporary one; in either case the measured anisotropy indicates that the mean free path for particle scattering is about 7 pc along the local magnetic field direction and probably about half this value in the perpendicular direction.