Search for 𝐶𝑃-Violating Neutrino Nonstandard Interactions with the NOvA Experiment
This Letter reports a search for charge-parity (𝐶𝑃) symmetry violating nonstandard interactions (NSI) of neutrinos with matter using the NOvA Experiment, and examines their effects on the determination of the standard oscillation parameters. Data from 𝜈 𝜇 ($\bar{𝜈}$ 𝜇 ) → 𝜈 𝜇 ($\bar{𝜈}$ 𝜇 ) and 𝜈 𝜇 ($\bar{𝜈}$ 𝜇 ) → 𝜈 𝑒 ( $\bar{𝜈}$ 𝑒 ) oscillation channels are used to measure the effect of the NSI parameters 𝜖 𝑒𝜇 and 𝜖 𝑒𝜏 . With 90% CL the magnitudes of the NSI couplings are constrained to be |𝜖 𝑒𝜇 | ≲0.3 and |𝜖 𝑒𝜏 | ≲ 0.4. A degeneracy at |𝜖 𝑒𝜏 | ≈ 1.8 is reported, and we observe that the presence of NSI limits sensitivity to the standard 𝐶𝑃 phase 𝛿 𝐶𝑃 .