Non-standard neutrino interactions as a solution to the NO$ν$A and T2K discrepancy
Sabya Sachi Chatterjee, Antonio Palazzo
备注：
9 pages, 6 figures, 1 table. Accepted for publication in PRL. One additional figure (S1) is presented in the Supplemental Material in addition to the PRL version
The latest data of the two long-baseline accelerator experiments NO$ν$A and T2K, interpreted in the standard 3-flavor scenario, display a discrepancy. A mismatch in the determination of the standard CP-phase $δ_{\mathrm {CP}}$ extracted by the two experiments is evident in the normal neutrino mass ordering. While NO$ν$A prefers values close to $δ_{\mathrm {CP}} \sim 0.8 π$, T2K identifies values of $δ_{\mathrm {CP}} \sim 1.4 π$. Such two estimates are in disagreement at more than 90$\%$ C.L. for 2 degrees of freedom. We show that such a tension can be resolved if one hypothesizes the existence of complex neutral-current non-standard interactions (NSI) of the flavor changing type involving the $e-μ$ or the $e-τ$ sectors with couplings $|\varepsilon_{eμ}| \sim |\varepsilon_{eτ}|\sim 0.2$. Remarkably, in the presence of such NSI, both experiments point towards the same common value of the standard CP-phase $δ_{\mathrm {CP}} \sim 3π/2$. Our analysis also highlights an intriguing preference for maximal CP-violation in the non-standard sector with the NSI CP-phases having best fit close to $ϕ_{eμ} \sim ϕ_{eτ}\sim 3π/2$, hence pointing towards imaginary NSI couplings.
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331 vector-like models with mirror fermions as a possible solution for the discrepancy in the b-quark asymmetries, and for the neutrino mass and mixing pattern
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The non-perturbative approach based on Bogoliubov compensation principle is applied to the calculation of a contribution to the muon $g-2$. Using the previous results on the spontaneous generation of the effective anomalous three-boson interaction the contribution is calculated and shown to be in agreement with the well-known discrepancy. The calculated quantity contains no adjusting parameters but the experimental values for the muon and the W-boson masses.
Non-Standard Neutrino Interactions at a Muon Collider Neutrino Detector
Deutsches Elektronen-Synchrotron DESY（德国电子同步加速器）；Department of Physics and Astronomy, University of California, Irvine（加州大学尔湾分校物理与天文系）；Centre for Cosmology, Particle Physics and Phenomenology (CP3), UCLouvain（天主教鲁汶宇宙学、粒子物理与现象学中心）；Faculty of Physics, University of Warsaw（华沙大学物理系）；Center for Particle Physics Siegen, University of Siegen（锡根大学粒子物理锡根中心）；PITT PACC, Department of Physics and Astronomy, University of Pittsburgh（匹兹堡大学物理与天文系皮特粒子物理与宇宙学中心）
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