Münster 2017 – wissenschaftliches Programm
T 107.3: Vortrag
Donnerstag, 30. März 2017, 17:15–17:30, H 2
A muon veto for the measurement of the downgoing neutrino flux with KM3NeT/ORCA — •Marco Volkert, Jannik Hofestädt, and Thomas Eberl — ECAP, Universität Erlangen-Nürnberg, 91058 Erlangen
By measuring the energy- and zenith-dependent oscillation probabilities of atmospheric neutrinos passing through Earth, it is possible to determine the hitherto unknown neutrino mass hierarchy. With this aim, the underwater Cherenkov detector ORCA is being built by the KM3NeT Collaboration in the Mediterranean deep sea.
The atmospheric muon flux entering the detector from the direction of the water surface is the main background for the detection of neutrinos. On the one hand, incorrectly reconstructed tracks of atmospheric muons distort the measurement of the upgoing atmospheric neutrino flux passing through Earth. On the other hand, this background crucially complicates the measurement of the downgoing atmospheric neutrino flux from above, which could be used for reducing the systematic uncertainties of the mass hierarchy measurement.
This talk presents a veto strategy for atmospheric muons developed for the determination of the downgoing atmospheric neutrino flux. A atmospheric muon contamination of about 1 % remains, while an effective mass for neutrinos of roughly 1.75 Mton for neutrino energies above 10 GeV is achieved. Furthermore, an investigation to which precision the atmospheric neutrino flux parameters can be determined is presented.