Dr. Francis Halzen, University of Wisconsin

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Presented in Collaboration with the Fermilab Users Annual Meeting

The IceCube project at the South Pole has melted eighty-six holes over 1.5 miles deep in the Antarctic icecap to be used as astronomical observatories. Into each hole is lowered a string knotted with basketball-sized light detectors that are sensitive to the shimmering blue light emitted in the surrounding clear ice when ghostly particles called neutrinos pass through the Earth. We have recently discovered a flux of neutrinos reaching us from the cosmos with energies more than a million times those of the neutrinos produced at Fermilab. They are astronomical messengers from the most violent processes in the universe; for example, giant black holes gobbling up stars in the heart of quasars and gamma-ray bursts, which are the biggest explosions since the Big Bang. We will describe the telescope and highlight its first scientific results.

Dr. Halzen is a theoretician studying problems at the interface of particle physics, astrophysics and cosmology. He is the principal investigator of the IceCube project and a professor of physics at the University of Wisconsin-Madison. Since 1987, he has been working on the AMANDA experiment, a first generation neutrino telescope at the South Pole. AMANDA observations represent a proof of concept for IceCube, a kilometer-scale observatory now completed and taking data.