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Detection of Accelerator-Produced Neutrinos at a Distance of 250 km

The K2K Collaboration·S. H. Ahn
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Abstract

The KEK to Kamioka long-baseline neutrino experiment (K2K) has begun its investigation of neutrino oscillations suggested by atmospheric neutrino observations. Twenty-eight neutrino events have been detected in coincidence with the expected arrival time of the beam in the 22.5 kt fiducial volume of Super--Kamiokande, the far detector at 250 km distance. The expectation is 37.8+3.5-3.8, derived using measurements of neutrino interactions in a near detector and extrapolation using a beam simulation validated by a measurement of pion kinematics after production and focusing. The background is of order 10^-3 events.

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The K2K Collaboration, S. H. Ahn. 2001-03-01. Detection of Accelerator-Produced Neutrinos at a Distance of 250 km. https://doi.org/10.1016/s0370-2693(01)00647-5

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