Analysis of IceCube Data at UW-Madison 2016-2019

University Of Wisconsin-Madison, Madison WI

Investigators

Abstract

Embedded deep in the ice cap at the South Pole, the IceCube Neutrino Observatory (ICNO) is the world's largest and most sensitive high energy neutrino telescope. It is a 1 billion-ton detector using the Antarctic ice as a detection medium for high energy atmospheric and astrophysical neutrinos. Most of the neutrinos observed by IceCube exhibit energies in the range expected for atmospheric neutrinos originating from decays of particles produced in extensive air showers by cosmic rays coming from nearby sectors of the Milky Way Galaxy. These may be used to measure the fundamental properties of neutrinos. At higher energies, astrophysical neutrinos are key probes of the high-energy universe. Because of their unique properties, neutrinos escape even dense regions, are not deflected by galactic or extra-galactic magnetic fields and traverse the photon-filled universe unhindered. Thus, neutrinos provide direct information about the dynamics and interiors of the powerful cosmic objects that may be the origins of high energy cosmic rays: supernovae, black holes, pulsars, active galactic nuclei and other extreme extragalactic phenomena. This award provides funding for the scientists at the University of Wisconsin-Madison for the scientific analysis of data taken with the IceCube neutrino detector. The study of neutrino oscillations and the ongoing correlation studies between the arrival directions of cosmic neutrinos and high-energy photons are only two of a large range of current analyses, illustrating that discoveries are at best in initial stages. The mystique of the South Pole environment and the compelling science of IceCube are an alluring mix. IceCube results have already enhanced scientific and technological understanding on many levels and have inspired the innovative capacity of a new generation of American scientists and engineers. The Madison group will continue to make IceCube science and resources available to existing education and outreach programs with a proven record of success. The group is also a partner of a new program, called "El Universo es Tuyo" (the Universe is Yours), to engage the Hispanic community in and around Madison in learning about research and STEM careers in astronomy and astrophysics. DeepCore, a densely instrumented infill array in the bottom half of the IceCube detector, has lowered the sensitivity threshold to 10 GeV. The Madison group participates in the development of analysis techniques that specialize to DeepCore data. They will result in improved measurements of the atmospheric oscillation parameters. The accumulating cosmic neutrino events indicate an enhancement of the flux below 100 TeV that may hint at another component in the cosmic neutrino spectrum.