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Latest Results from the K2K experiment

A. K. Ichikawa
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Abstract

The KEK to Kamioka long-baseline neutrino experiment (K2K) is the first accelerator-based experiment with hundreds of km neutrino path length. K2K focuses on the study of the existence of neutrino oscillations in $ν_μ$ disappearance that is observed in atmospheric neutrinos. With nearly pure muon neutrino beam produced with $5.6\times 10^{19}$ protons from 12 GeV PS on target, 56 neutrino events have been observed at Super-Kamiokande, the far detector at 250 km distance. The expectation is $80.6^{+7.3}_{-8.0}$ derived from the measurement at the near site. The experiment expects to accumulate $10^{20}$ protons on target, providing sufficient statistics to study neutrino oscillations by spectral analysis for $ν_μ$ disappearance.

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A. K. Ichikawa. 2002-06-17. Latest Results from the K2K experiment. https://arxiv.org/abs/hep-ex/0206037

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