HIGH-ENERGY PARTICLES FROM COSMIC SOURCES

In this review it will be attempted to briefly cover some of the recent developments in the observation of photons and neutrinos to constrain models on the origin and acceleration of cosmic rays. It appears that EGRET on board of CGRO provides most valuable new data in that context. Data from high energy air-shower arrays and Tscherenkov telescopes add to the picture although not yet strong enough to really decipher the origin of cosmic rays. Searches for high energy neutrinos in underground detectors put further constraints on models in particular on possible origins of the highest energy cosmic rays. Most spectacular is the EGRET observation of a particular gamma ray burst deepening the mystery of the gamma ray burst phenomenon. Further ongoing observations of cosmic ray photons and neutrinos should get us closer to an understanding of the origin of cosmic rays.