Ultrahigh Energy Particle Astrophysics at IceCube

Ohio State University, The, Columbus OH

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. The PI effectively mentors junior faculty, including women and members of underrepresented minorities and is committed to enhancing diversity in STEM fields through participation in an NSF ADVANCE program. The project provides an excellent environment for students and postdocs, who are well-equipped to contribute to scientific and economic progress in academia, government, and industry. The award includes development of planetarium content on high energy astrophysics, cosmic rays, and neutrinos. This will bring the excitement of cutting-edge research to young students and the community. IceCube incorporates an air shower detector, IceTop, a water Cherenkov detector which covers the energy range from 10^15 to 10^18 eV where hadronic interactions are better constrained by data from the Large Hadron Collider. The analysis work funded by this award focuses on the problem of disentangling the composition of the highest energy cosmic rays from hadronic interactions. The behavior of ultrahigh energy cosmic ray air showers is not well-described by current models of hadronic interactions. Resolution of this problem may result in transformative improvements in our understanding of interactions beyond the reach of terrestrial accelerators.