First measurement of muon-neutrino disappearance in NOvA

TL;DR

This paper presents the first measurement of muon-neutrino disappearance by NOvA, providing key neutrino oscillation parameters with a significant dataset, and comparing results for both normal and inverted mass hierarchies.

Contribution

It is the first to measure muon-neutrino disappearance using NOvA detectors, estimating oscillation parameters with a large exposure and analyzing both mass hierarchies.

Findings

Measured m^2_{32} = (2.52^{+0.20}_{-0.18}) imes 10^{-3} eV^2

Determined os^2 heta_{23} in the range 0.38-0.65 at 68% CL

Identified two statistically-degenerate best-fit points for os^2 heta_{23}

Abstract

This paper reports the first measurement using the NOvA detectors of $\nu_\mu$ disappearance in a $\nu_\mu$ beam. The analysis uses a 14 kton-equivalent exposure of $2.74 \times 10^{20}$ protons-on-target from the Fermilab NuMI beam. Assuming the normal neutrino mass hierarchy, we measure $\Delta m^{2}_{32}=(2.52^{+0.20}_{-0.18})\times 10^{-3}$ eV$^{2}$ and $\sin^2\theta_{23}$ in the range 0.38-0.65, both at the 68% confidence level, with two statistically-degenerate best fit points at $\sin^2\theta_{23} = $ 0.43 and 0.60. Results for the inverted mass hierarchy are also presented.