A twozone propagation model applied to radioactive cosmic ray isotopes.
Abstract
The astrophysical interpretations of all the cosmic ray observations depend very much on the model which one uses to describe the propagation of cosmic rays through the interstellar space. Usually one treats the galaxy as a 'leaky box' and considers the cosmic rays to be in spatial and temporal equilibrium. One further assumes that the interstellar matter is homogeneously distributed. Various attempts have been made to deduce this mean matter density by means of the surviving fraction alpha of radioactive secondary isotopes in order to pinpoint the regions where the cosmic rays may mainly reside. In this paper it is shown that such attempts lead to ambiguous conclusions if one accepts a more realistic picture of a nonhomogeneous distribution of interstellar matter. For these investigations a Monte Carlo Propagation Program has been developed in order to follow the fate of individual cosmic ray particles through space by varying the densities and mean path lengths in different regions. The effect on the surviving fraction alpha has been quantitatively calculated and discussed.
 Publication:

Astronomy and Astrophysics
 Pub Date:
 May 1979
 Bibcode:
 1979A&A....75..114S
 Keywords:

 Cosmic Rays;
 Particle Diffusion;
 Propagation (Extension);
 Radioactive Isotopes;
 Astronomical Models;
 Monte Carlo Method;
 Secondary Cosmic Rays;
 Space Radiation;
 Cosmic Rays:Particles;
 Cosmic Rays:Propagation