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T2K (Tokai to Kamioka) is a long baseline neutrino experiment with the primary goal of measuring the neutrino mixing angle θ 13 . It uses a muon neutrino beam, produced at the J-PARC accelerator facility in Tokai, sent through a near detector complex on its way to the far detector, Super-Kamiokande. Appearance of electron neutrinos at the far detector due to oscillation is used to measure the value of θ 13 .

We present measurements of nu(mu) disappearance in K2K, the KEK to Kamioka long-baseline neutrino oscillation experiment. One-hundred and twelve beam-originated neutrino events are observed in the fiducial volume of Super-Kamiokande with an expectation of 158.1(-8.6)(+9.2) events without oscillation. A distortion of the energy spectrum is also seen in 58 single-ring muonlike events with reconstructed energies. The probability that the observations are explained by the expectation for no neutrino oscillation is 0.0015% (4.3 sigma). In a two-flavor oscillation scenario, the allowed Delta m(2) region at sin(2)2 theta=1 is between 1.9 and 3.5x10(-3) eV(2) at the 90% C.L. with a best-fit value of 2.8x10(-3) eV(2)

The T2K experiment is a long baseline neutrino oscillation experiment. Its main goal is to measure the last unknown lepton sector mixing angle θ13θ13 by observing νeνe appearance in a νμνμ beam. It also aims to make a precision measurement of the known oscillation parameters, View the MathML sourceΔm232 and sin22θ23sin22θ23, via νμνμ disappearance studies. Other goals of the experiment include various neutrino cross-section measurements and sterile neutrino searches. The experiment uses an intense proton beam generated by the J-PARC accelerator in Tokai, Japan, and is composed of a neutrino beamline, a near detector complex (ND280), and a far detector (Super-Kamiokande) located 295 km away from J-PARC. This paper provides a comprehensive review of the instrumentation aspect of the T2K experiment and a summary of the vital information for each subsystem

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This article reports an empirical study of a 15-week study-abroad program for Japanese university students, examining changes in the students’ beliefs about language learning (measured by means of a questionnaire) and in their English proficiency (measured by means of the TOEFL). The results showed statistically significant changes in the students’ beliefs relating to analytic language learning, experiential language learning and self-efficacy/confidence during the study-abroad period. Statistically significant gains in proficiency are also reported. However, Pearson product moment correlations between the students’ responses to the Belief Questionnaire and their TOEFL scores both before and after the study-abroad period were weak and generally statistically non-significant. The results are discussed in relation to study-abroad programs and also to the role of learner beliefs in second language learning.

We report a measurement of muon-neutrino disappearance in the T2K experiment. The 295-km muon-neutrino beam from Tokai to Kamioka is the first implementation of the off-axis technique in a long-baseline neutrino oscillation experiment. With data corresponding to 1.43×10 20 protons on target, we observe 31 fully-contained single µ-like ring events in Super-Kamiokande, compared with an expectation of 104 ± 14 (syst) events without neutrino oscillations. The best-fit point for two-flavor νµ → ντ oscillations is sin 2 (2θ23) = 0.98 and |∆m 2 32 | = 2.65 × 10 −3 eV 2 . The boundary of the 90% confidence region includes the points (sin 2 (2θ23), |∆m 2 32 |) = (1.0, 3.1×10 −3 eV 2 ), (0.84, 2.65×10 −3 eV 2 ) and (1.0, 2.2×10 −3 eV 2 ).