VU Physics and Astronomy Colloquium

Friday, April 17, at 3:20 PM in NSC 224. Join us for refreshments in NSC 231 at 3:05 PM.

"Cosmic Rays at the Bottom of the World"

John P. Wefel (VU '66), Department of Physics and Astronomy, Lousiana State University

Cosmic rays, those elusive particles arriving at Earth from elsewhere in our Galaxy with energies far above those achievable in terrestrial accelerators, may hold the key to understanding the high-energy processes that drive the evolution of galaxies such as our Milky Way. Previous work at low energy, from balloons and satellites, has revealed much about the nature of this cosmic radiation, but the challenge is to move to the very high-energy regime (VHE: 0.1– 100 TeV) to search for signatures of the sources. The Advanced Thin Ionization Calorimeter (ATIC) Balloon Experiment was constructed for this task and has had three successful flights from Antarctica. In addition to describing the instrument, results from the three ATIC flights will be presented, and compared to previous data as well as to astrophysical source models.