Monday, October 6, 2008, Joint Physics Colloquium, 4:30 PM, Wean 7500, CMU

Francis Halzen

Department of Physics, University of Wisconsin, Madison, WI 53706

"High-Energy Neutrino Astronomy: Towards a Kilometer-Scale Neutrino Observatory."

Abstract:

Kilometer-scale neutrino detectors such as IceCube are discovery instruments covering nuclear and particle physics, cosmology and astronomy. Examples of their multidisciplinary missions include the search for the particle nature of dark matter and for additional small dimensions of space. In the end, their conceptual design is very much anchored to the observational fact that Nature produces photons and protons with energies in excess of one hundred and one hundred million Terraelectronvolts, respectively. The cosmic ray connection sets the scale of cosmic neutrino fluxes. The problem has been to develop a robust and affordable technology to build the kilometer-scale neutrino detectors required to do the science. The AMANDA telescope transforming ultra-clear deep Antarctic ice into a Cherenkov detector of muons and showers initiated by neutrinos of all three flavors, has met this challenge. Having collected more than 6000 well-reconstructed muon neutrinos of 50 GeV ~ 500 TeV energy, AMANDA represents a proof of concept for the ultimate kilometer-scale neutrino observatory, IceCube, now half complete and already producing results exceeding in sensitivity seven years of AMANDA data.