Acta Physica Polonica B
Proceedings Supplement

Vol. 1, No. 2, February 2008, page 359

Progress in Ultra High Energy Cosmic Ray Studies

This is a review of the experimental data concerning the energy spectrum, the arrival distribution and the composition of cosmic rays with energies \geq 10¹⁷ eV. We discuss conditions for production of cosmic rays and expected effects for observation. Main recent results issued by observation of cosmic ray at high and very high energy will also be presented.

PACS numbers: 95.55.Vj, 95.85.Ry, 98.70.Sa