Physics colloquium-“Particle Physics with Air Showers at the IceCube Neutrino Observatory”

Dennis Soldin

University of Utah, Department of Physics & Astronomy

Abstract: Cosmic rays are charged particles that enter the Earth’s atmosphere where they interact with air molecules at energies of more than 10 times the center-of-mass energy at the Large Hadron Collider at CERN. These interactions produce particle cascades in the atmosphere, so-called extensive air showers, which can be measured at the ground. The properties of the initial cosmic ray, such as its energy and mass, are inferred indirectly from the particles measured at the ground and their interpretation strongly relies on simulations of the shower development. In recent years, however, various measurements have shown large discrepancies with respect to current model predictions, indicating shortcomings in our understanding of particle physics which can only be explained in the context of unconventional or new physics. The IceCube Neutrino Observatory (IceCube) is located at the geographic South Pole and it consists of a cubic-kilometer Cherenkov detector deep in the Antarctic ice, accompanied by a surface detector array. This hybrid detector setup yields various opportunities to study cosmic rays and thereby reduce the remaining model uncertainties. In this talk, I will review the current state of the field and present recent results of cosmic-ray measurements with IceCube. In particular, I will highlight IceCube’s unique opportunities to provide important information about particle interactions in extensive air showers. I will discuss the synergies between cosmic-ray and particle physics in the multi-messenger era and conclude by showing how measurements with IceCube open a new window for interdisciplinary studies of fundamental physics at the frontier between astroparticle and particle physics.

Pre-seminar snacks will be offered in CoorsTek 140/150 from 3:30pm-4:00pm.