Abstract not found

A long-baseline neutrino-oscillation experiment using a well-defined neutrino beam is in preparation at KEK. Neutrinos generated at KEK will be detected by the Super-Kamiokande detector 250 km away. The design of the neutrino beam line, beam monitors and detector are briefly presented. The sensitivities for neutrino oscillations are also discussed. §1. Overview In recent years, several underground neutrino observatories 1)-3) have reported that the atmospheric neutrino ratio, R ≡ (νµ + ¯νµ)/(νe + ¯νe), is significantly smaller than the theoretical expectations. This “atmospheric neutrino anomaly ” can be explained by a neutrino oscillation hypothesis with an oscillation parameter region of ∆m 2 ∼ 10 −2 eV 2 and sin 2 2θ ∼ 1. The atmospheric neutrino anomaly has also been confirmed by a preliminary result from the Super-Kamiokande experiment, 4), which shows a rather smaller ∆m 2 than does Kamiokande. The K2K experiment 5) (formerly called the KEK-PS E362 experiment) is the first long-baseline neutrino-oscillation experiment using an artificial neutrino beam. The almost pure νµ beam from π + decays is generated in the KEK 12-GeV Proton

The “baseline setup ” for a possible, beyond T2K, next generation long baseline experiment along the J-PARC neutrino beam produced at Tokai, assumes two very large deep-underground Water Cerenkov imaging detectors of about 300 kton fiducial each, located one in Korea and the other in Kamioka

New Physics’, ha sido realizada bajo su dirección en el Departamento de F́ısica Teórica de la Universidad de Valencia por David Vanegas Forero, y que constituye su tesis doctoral para optar al grado de Doctor en F́ısica. Para que aśı conste, en cumplimiento de la legislación vigente, presentan en el Departa-mento de F́ısica Teórica de la Universidad de Valencia la referida Tesis Doctoral, y firman el presente certificado.

-dicted by most stellar collapse calculations [ 1-3]. Unfortunately this pulse is virtually undetectable in the present water Cerenkov counters. Thus the eleven and eight neutrinos from SN 1987A detected by the Kamioka II [ 4] and IMB [ 5] detectors respectively, are believed to originate from the thermal %, emit

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of the 37 Cl, SAGE/GALLEX, and Kamioka II/III experiments are consistent with an unexpected pattern of neutrino fluxes, φ(pp) ∼ φ SSM (pp)

be set on a linear or quadratic violation of Lorentz invariance in the propagation of energetic neutrinos, v/c = [1 ± (E/MνQG1)] or [1 ± (E/MνQG2) 2], using data from supernova explosions and the OPERA long-baseline neutrino experiment. Using the SN1987a neutrino data from the Kamioka II, IMB and Baksan