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The extension of the minimal standard model by three right-handed sterile neutrinos with masses smaller than the electroweak scale (&ngr;MSM) is discussed in a Q6 flavor symmetry framework. The lightness of the keV sterile neutrino and the near mass degeneracy of two heavier sterile neutrinos are naturally explained by exploiting group properties of Q6. A normal hierarchical mass spectrum and an approximately &mgr;-&tgr; symmetric mass matrix are predicted for three active neutrinos. Nonzero &thgr;13 can be obtained together with a deviation of &thgr;23 from the maximality, where both mixing angles are consistent with the latest global data including T2K and MINOS results. Furthermore, the tiny active-sterile mixing is related to the mass ratio between the lightest active and lightest sterile neutrinos. [ABSTRACT FROM AUTHOR]

We have examined the impact of new Daya Bay, Double Chooz, and RENO measurements on global fits of reactor antineutrino flux data to a variety of hypotheses regarding the origin of the reactor antineutrino anomaly. In comparing RENO and Daya Bay measurements of inverse beta decay (IBD) yield versus 239Pu fission fraction, we find differing levels of precision in measurements of time-integrated yield and yield slope, but similar central values, leading to modestly enhanced isotopic IBD yield measurements in a joint fit of the two datasets. In the absence of sterile neutrino oscillations, global fits to all measurements now provide 3σ preference for incorrect modeling of specific fission isotopes over common mismodeling of all beta-converted isotopes. If sterile neutrino oscillations are considered, global IBD yield fits provide no substantial preference between oscillation-including and oscillation-excluding hypotheses: hybrid models containing both sterile neutrino oscillations and incorrect 235U or 239Pu flux predictions are favored at only 1σ-2σ with respect to models where 235U, 238U, and 239Pu are assumed to be incorrectly predicted. [ABSTRACT FROM AUTHOR]

We present the results of global analyses of short-baseline neutrino oscillation data in 3 + 1, 3 + 2 and 3+1 + 1 neutrino mixing schemes. We show that the data do not allow us to abandon the simplest 3 + 1 scheme in favor of the more complex 3 + 2 and 3 + 1 + 1 schemes. We present the allowed region in the 3 + 1 parameter space, which is located at Δm41² between 0.82 and 2.19 eV² at 3s. The case of no oscillations is disfavored by about 6s, which decreases dramatically to about 2s if the Liquid Scintillating Neutrino Detector (LSND) data are not considered. Hence, new high-precision experiments are needed to check the LSND signal. [ABSTRACT FROM AUTHOR]

We discuss the implications for short-baseline electron neutrino disappearance in the 3 + 1 mixing scheme of the recent Troitsk bounds on the mixing of a neutrino with mass between 2 and 100 eV. Considering the Troitsk data in combination with the results of short-baseline ve and ve disappearance experiments, which include the reactor and Gallium anomalies, we derive a 2σ allowed range for the effective neutrino squared-mass difference between 0.85 and 43 eV2. The upper bound implies that it is likely that oscillations in distance and/or energy can be observed in radioactive source experiments. It is also favorable for the ICARUS@CERN experiment, in which it is likely that oscillations are not washed out in the near detector. We discuss also the implications for neutrinoless double-β decay. [ABSTRACT FROM AUTHOR]

We present the results on the radius of the neutron distribution in 40Ar, on the low-energy value of the weak mixing angle, and on the electromagnetic properties of neutrinos obtained from the analysis of the coherent neutrino-nucleus elastic scattering data in argon recently published by the COHERENT Collaboration, taking into account proper radiative corrections. We present also the results of the combined analysis of the COHERENT argon and cesium-iodide data for the determination of the low-energy value of the weak mixing angle and the electromagnetic properties of neutrinos. In particular, the COHERENT argon data allow us to improve significantly the only existing laboratory bounds on the electric charge qμμ of the muon neutrino and on the transition electric charge qμτ. [ABSTRACT FROM AUTHOR]

We present an updated analysis of the coherent neutrino-nucleus elastic scattering data of the COHERENT experiment, taking into account the new quenching factor published recently in [Phys. Rev. D 100, 033003 (2019)]. Through a fit of the COHERENT time-integrated energy spectrum, we show that the new quenching factor leads to a better determination of the average rms radius of the neutron distributions of 133Cs and 127I, while in combination with the atomic parity violation (APV) experimental results, it allows us to determine a data-driven APV measurement of the low-energy weak mixing angle in very good agreement with the Standard Model prediction. We also find a 3.7σ evidence of the suppression of coherence due to the nuclear structure. Neutrino properties are better constrained by considering the COHERENT time-dependent spectral data, that allow us to improve the bounds on the neutrino charge radii and magnetic moments. We also present for the first time constraints on the neutrino charges obtained with coherent neutrino-nucleus elastic scattering data. In particular, we obtain the first laboratory constraints on the diagonal charge of νμ and the νμ-ντ transition charge. [ABSTRACT FROM AUTHOR]

Coherent elastic neutrino-nucleus scattering is a powerful probe of neutrino properties, in particular of the neutrino charge radii. We present the bounds on the neutrino charge radii obtained from the analysis of the data of the COHERENT experiment. We show that the time information of the COHERENT data allows us to restrict the allowed ranges of the neutrino charge radii, especially that of νμ. We also obtained for the first time bounds on the neutrino transition charge radii, which are quantities beyond the standard model. [ABSTRACT FROM AUTHOR]