ASTROPHYSICAL ACCELERATION MODELS FOR THE HIGHEST ENERGY COSMIC RAYS

Todor Stanev --- Bartol Research Institute University of Delaware, Newark, DE 19716

2.30 pm Monday April 24

We discuss the consequences of the traditional models for acceleration of the highest energy cosmic rays in astrophysical shocks. These include acceleration at shocks in radio galaxies, gamma ray bursts and on large scale shocks in the extragalactic space. The distance to the potential sources is limited because of proton energy losses in interactions on the microwave background. One expects that the existence of nearby sources would lead to anisotropy of the arrival directions for these particles, depending on the degree of scattering in the extragalactic magnetic fields. The limited experimental data do not suggest strong large scale anisotropy, although 1% level effects are present in the sample.