Wisconsin IceCube Particle Astrophysics Center &
Department of Physics, University of Wisconsin-Madison
Thursday, March 21st 2024, 19:00
Stephen Leacock Building, Leacock Auditorium (room 132)
IceCube: Opening a Neutrino Window on the Universe from the South Pole
The IceCube project at the South Pole melted 86 holes 2.5 kilometer deep in
the Antarctic icecap to construct an enormous astronomical observatory. The
experiment discovered a flux of neutrinos from deep space with energies
more than a million times those of neutrinos produced at accelerator
laboratories. These cosmic neutrinos are created in some of the most violent
processes in the universe since the Big Bang and originate in the cosmic
particle accelerators that are still enigmatic sources of cosmic rays. This
lecture will discuss the IceCube neutrino telescope and the discovery of
high-energy neutrinos of cosmic origin. It will highlight the recent discovery
that high-energy neutrinos—and cosmic rays—originate in sources powered
by rotating supermassive black holes.
Friday, March 22nd 2024, 15:30
Ernest Rutherford Physics Building, Keys Auditorium (room 112)
IceCube: The First Decade of Neutrino Astronomy
Below the geographic South Pole, the IceCube project has transformed one cubic
kilometer of natural Antarctic ice into a neutrino detector. IceCube detects
more than 100,000 neutrinos per year in the GeV to 10 PeV energy range. Among
those, we have isolated a flux of high-energy neutrinos originating beyond our
Galaxy, with an energy flux that is comparable to that of the extragalactic
high-energy photon flux observed by the NASA Fermi satellite. With a decade
of data, we have identified their first sources, which point to the obscured
dense cores associated with the supermassive black holes at the centers of
active galaxies as the origin of high-energy neutrinos and high-energy cosmic
rays. We recently also observed neutrinos originating in our own Milky Way
which is, interestingly, not a prominent feature in the neutrino sky.
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