Improving the neutrino mass hierarchy identification with inelasticity measurement in PINGU and ORCA

Understand

Multi-megaton scale under ice and underwater detectors of atmospheric neutrinos with few GeV's energy threshold (PINGU, ORCA) open up new possibilities in the determination of neutrino properties, and in particular the neutrino mass hierarchy.

• With a dense array of optical modules it will be possible to determine the inelasticity, $y$, of the charged current $\nu_\mu$ events in addition to the neutrino energy $E_\nu$ and the muon zenith angle $\theta_\mu$.
• The discovery potential of the detectors will substantially increase with the measurement of $y$.
• It will enable (i) a partial separation of the neutrino and antineutrino signals; (ii) a better reconstruction of the neutrino direction; (iii) the reduction of the neutrino parameters degeneracy; (iv) a better control of systematic uncertainties; (v) a better identification of the $\nu_\mu$ events.