Measurement of Atmospheric Neutrino Oscillations with IceCube/DeepCore in Its 79-string Configuration
Abstract
With its low-energy extension DeepCore, the IceCube Neutrino Observatory at the Amundsen-Scott South Pole Station is able to detect neutrino events with energies as low as 10 GeV. This permits the investigation of flavor oscillations of atmospheric muon neutrinos by observing their zenith direction and energy. Maximum disappearance is expected for vertically upward moving muon neutrinos at around 25 GeV. A recent analysis has rejected the non-oscillation hypothesis with a significance of about 5 standard deviations based on data obtained with IceCube while it was operating in its 79-string configuration [1]. The analysis presented here uses data from the same detector configuration, but implements a more powerful approach for the event selection, which yields a dataset with significantly higher statistics of more than 8 000 events. We present new results based on a likelihood analysis of the two observables zenith angle and energy. The non-oscillation hypothesis is again rejected with a significance of about 5.1 standard deviations. In the 2-flavor approximation, our best-fit oscillation parameters are (2.45±0.7). 103eV2 and sin2 (2023) 1.01,5.
- Publication:
-
International Cosmic Ray Conference
- Pub Date:
- 2013
- Bibcode:
- 2013ICRC...33.1252E
- Keywords:
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- IceCube DeepCore;
- atmospheric neutrino oscillations;
- v~ disappearance.