From Oscillation Dip to Oscillation Valley in Atmospheric Neutrino Experiments
Date:
Conference: Virtual Mini-Workshop on Neutrino Theory, Sep 21 - 23, 2020
Presentation mode: Online
Abstract: Atmospheric neutrino experiments can show the “oscillation dip” feature in data, due to their sensitivity over a large L/E range. In experiments that can distinguish between neutrinos and antineutrinos, like INO, oscillation dips can be observed in both these channels separately. We present a data-driven approach − that uses the asymmetry in the up and down events, binned in the reconstructed L/E of muons − to demonstrate the dip, thereby confirming the oscillation hypothesis. We further propose, for the first time, the identification of an “oscillation valley” in the (E&muon;−cosθ&muon;) plane, feasible for detectors like INO having excellent muon energy and direction resolutions. We illustrate how this two-dimensional valley offers a clear visual representation and test of the L/E dependence, the alignment of the valley quantifying the atmospheric mass-squared difference.