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This paper reports measurements of final-state proton multiplicity, muon and proton kinematics, and their correlations in charged-current pionless neutrino interactions, measured by the T2K ND280 near detector in its plastic scintillator (C 8 H 8 ) target. The data were taken between years 2010 and 2013, corresponding to approximately 6 × 10 20 protons on target. Thanks to their exploration of the proton kinematics and of imbalances between the proton and muon kinematics, the results offer a novel probe of the nuclear-medium effects most pertinent to the (sub-)GeV neutrino-nucleus interactions that are used in accelerator-based long-baseline neutrino oscillation measurements. These results are compared to many neutrino-nucleus interaction models which all fail to describe at least part of the observed phase space. In case of events without a proton above a detection threshold in the final state, a fully consistent implementation of the local Fermi gas model with multinucleon interactions gives the best description of the data. In the case of at least one proton in the final state, the spectral function model agrees well with the data, most notably when measuring the kinematic imbalance between the muon and the proton in the plane transverse to the incoming neutrino. Within the models considered, only the existence of multinucleon interactions are able to describe the extracted cross section within regions of high transverse kinematic imbalance. The effect of final-state interactions is also discussed.

Interest in dynamic behaviour of carriers in organic materials is motivated by possible applications that include organic thin film transistors, organic electroluminescent (EL) devices, and organic photo-conductors. It can also provide insight into modelling of carrier transport and trapping in organic semiconductors and insulators Here, we employ advanced SHG technique to probe and visualize real carrier motion in organic materials. This is a time-resolved microscopic optical SHG (TRM-SHG) technique that allows direct and selective probing of dynamic carrier motion in organic materials. TRM-SHG experiments using pentacene field effect transistors (FET) revealed dynamic changes of SHG intensity profiles arising from pentacene. Carrier velocity in organic solids is thus determined from the visualized carrier motion. We anticipate that this direct visualization technique will find wide application in the illustration of space charge field formation in organic and inorganic materials, including biomaterials and polymers.

The T2K experiment reports an updated analysis of neutrino and antineutrino oscillations in appearance and disappearance channels. A sample of electron neutrino candidates at Super-Kamiokande in which a pion decay has been tagged is added to the four single-ring samples used in previous T2K oscillation analyses. Through combined analyses of these five samples, simultaneous measurements of four oscillation parameters, jΔm 2 32 j, sin 2 θ 23 , sin 2 θ 13 , and δ CP and of the mass ordering are made. A set of studies of simulated data indicates that the sensitivity to the oscillation parameters is not limited by neutrino interaction model uncertainty. Multiple oscillation analyses are performed, and frequentist and Bayesian intervals are presented for combinations of the oscillation parameters with and without the inclusion of reactor constraints on sin 2 θ 13. When combined with reactor measurements, the hypothesis of CP conservation (δ CP ¼ 0 or π) is excluded at 90% confidence level. The 90% confidence region for δ CP is ½−2.95; −0.44 (½−1.47; −1.27) for normal (inverted) ordering. The central values and 68% confidence intervals for the other oscillation parameters for normal (inverted) ordering are Δm 2 32 ¼ 2.54 AE 0.08ð2.51 AE 0.08Þ × 10 −3 eV 2 =c 4 and sin 2 θ 23 ¼ 0.55 þ0.05 −0.09 (0.55 þ0.05 −0.08), compatible with maximal mixing. In the Bayesian analysis, the data weakly prefer normal ordering (Bayes factor 3.7) and the upper octant for sin 2 θ 23 (Bayes factor 2.4).

The pentacene field effect transistor (FET) is analyzed as a Maxwell-Wagner effect element. As a result of the Maxwell-Wagner effect, carriers injected from source electrode are accumulated at the interface between pentacene and SiO2-gate insulator. They are then conveyed along the FET channel by the electric field formed between source and drain electrodes. The drain current Ids shows characteristic behavior depending on the force of the electric field. The transit time and charging time of injected carriers are key parameters to specify FET characteristics ruled by the Maxwell-Wagner effect. Results also show that our pentacene FET characteristics are well explained based on the present theoretical analysis.