First inclusive triple-differential measurement of the muon-antineutrino charged-current cross section using the NOvA Near Detector

Abstract

We present the first measurement of the triple-differential muon antineutrino charged-current inclusive cross section, using the NOvA Near Detector and $12.5 \times 10^{20}$ protons on target in the NuMI beam. This sample of muon antineutrino interactions is the largest ever published, with approximately 1 million selected muon antineutrino events. The triple-differential cross section is measured in the final-state kinetic energy, the scattering angle, and the available energy of the interaction. The measurement enables phase-space regions populated by differing neutrino reaction processes to be isolated and the transition regions between them to be defined. The results are compared with the predictions of the main event generators used in the neutrino community and we observe energy- and angle-dependent discrepancies across a broad range of energies and interaction types

Figures (7)

• Figure 1: Event distribution of the available energy in the selected sample, broken down by interaction types. Only statistical uncertainties are included in the error bars. The simulation histogram is obtained with GENIE 3.0.6 NOvA Tune v2.
• Figure 2: Flux-integrated triple differential cross-section measurements in panels of $\cos{\theta}_{\mu}$. Error bars include statistical and systematic uncertainties. The predictions from GENIE 3.0.6 NOvA Tune v2 in each $E_{\text{avail}}$ region are shown in various colors.
• Figure 3: Comparisons of our measurements to various GENIE CMCs, and to the neutrino generators NuWro 21.09.02 (2022) PhysRevC.86.015505, NEUT 5.7.0 (2023) Hayato_2021, and GiBUU (2023) BUSS20121PhysRevD.109.033008. See Tab. \ref{['tab:generators']} for a summary of the models used in these generators. Each plot shows the ratio of the prediction to our measurement. In the left column, the differential cross sections are integrated over $\cos{\theta}_{\mu}$ and shown vs. $T_{\mu}$. In the right column, the differential cross sections are integrated over $T_{\mu}$ and shown vs. $\cos{\theta}_{\mu}$. Each row represents one of the $E_{\text{avail}}$ bins.
• Figure S1: Signal purity vs. of $T_{\mu}$ in panels of $\cos \theta_\mu$. Each color represents a range of $E_{\text{avail}}$.
• Figure S2: Selection efficiency vs. $T_{\mu}$ in panels of $\cos \theta_\mu$. Each color represents a range of $E_{\text{avail}}$.