Abstract
Abstract
The galactic cosmic rays are high-energy particles that reach us from all directions of the vast universe. Their transport in the interplanetary medium is well described by the transport equation, first derived by Parker in 1965. An approximate solution of the cosmic ray transport equation for 1 AU is used to construct a simplified, semi-empirical model of the cosmic ray spectrum. The model parameters are obtained by fitting the proton spectra of the PAMELA experiment. The values of the model parameters are presented for the period 2006-2014, which includes the solar minimum between cycles 23 and 24 and the maximum phase of cycle 24. Our analysis shows that the proposed semi-empirical model agrees approximately well with the force-field approximation to the cosmic ray transport equation.