Physics Colloquium

"The observation of the GZK suppression in ultra-high energy cosmic rays"

Presented by Pierre Sokolsky, University of Utah

Tuesday, March 11, 2008, 3:30 pm — Large Seminar Room, Bldg. 510

Fourty years after the discovery of the 2.7 deg. black body radiation we can finally report on the definitive observations by the HiRes and Auger experiments of the inelastic interaction of ultra-high energy particles with the microwave photons. This interaction was proposed by Greisen, Zatsepin and Kuzmin within a year of the microwave background discovery.
The effect severely restricts the horizon for the highest energy charged particles. Recent claims of correlation of arrival directions of these particles with nearby AGN's will also be examined.

Hosted by: Helio Takai

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