Special Reviews

Ultrahigh-Energy Cosmic Rays: Physics and Astrophysics at Extreme Energies

+ See all authors and affiliations

Science  05 Jan 2001:
Vol. 291, Issue 5501, pp. 73-79
DOI: 10.1126/science.291.5501.73

You are currently viewing the abstract.

View Full Text


The origin of cosmic rays is one of the major unresolved questions in astrophysics. In particular, the highest energy cosmic rays observed have macroscopic energies up to several 1020electron volts and thus provide a probe of physics and astrophysics at energies unattained in laboratory experiments. Theoretical explanations range from astrophysical acceleration of charged particles, to particle physics beyond the established standard model, and processes taking place at the earliest moments of our universe. Distinguishing between these scenarios requires detectors with effective areas in the 1000-square-kilometer range, which are now under construction or in the planning stage. Close connections with γ-ray and neutrino astrophysics add to the interdisciplinary character of this field.

View Full Text

Related Content