COLÓQUIO DO DEPARTAMENTO DE FÍSICA MATEMÁTICA
DIA 28/04/2015 - 11H - SALA JAYME TIOMNO
"Neutrino Astronomy with IceCube"
Dr. Boris Panes (DFMA-IFUSP)
Abstract: The IceCube experiment (IC) takes advantage of the transparent and abundant ice present at the Earth South Pole in order to be able to capture the tiny flux of neutrinos which is expected at very high energies. Indeed, given the huge dimensions of the detector ice volume it is possible to detect incoming neutrinos with energies covering from the TeV scale up to the tens of PeV (for comparison the LHC c.o.m. energy is 14 TeV). Moreover, IC is able to reconstruct the direction and, to some extent, the flavor of the incoming neutrinos. The events detected by IC may arise from neutrinos originated from the interaction of cosmic rays with the Earth atmosphere, misidentified atmospheric muons or astrophysical neutrinos produced in the intergalactic media. Interestingly, from the current knowledge about the flux of cosmic rays and their interaction with the atmosphere, it is known that the contributions of atmospheric neutrinos and misidentified muons are actually important only be!
low 60 TeV and they become negligible above this energy scale. Then, most of the detected neutrinos at higher energies must be linked to some astrophysical source. Indeed, after three years of time exposure, IC has confirmed the existence of astrophysical neutrinos with more than five-sigma confidence level. This crucial piece of information allows us to study a variety of astrophysical scenarios of neutrino production, including unstable Dark Matter scenarios, but also some fundamental properties in the neutrino sector which are still unclear. Although the statistics is still insufficient in order to obtain clear answers at the moment, it is expected that in the future this experiment is going to increase their detection sensibility (time exposure, effective volume and performance of detection) at least one order of magnitude. Therefore, we should be confident that new and interesting observations, with a deep impact on fundamental physics, are still to come.
