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Current status of K2K long-baseline neutrino-oscillation experiment

Yuichi Oyama
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Abstract

The K2K (KEK to Kamioka) long-baseline neutrino-oscillation experiment was successfully started in early 1999. A total intensity of 7.20 x 10^18 protons on target, which is about 7% of the goal of the experiment, was accumulated in 39.4 days of data-taking in 1999. We obtained 3 neutrino events in the fiducial volume of the Super-Kamiokande detector, whereas the expectation based on observations in the front detectors is 12.3 +1.7/-1.9. An analysis of oscillation searches from the view points of absolute event numbers, distortion of neutrino energy spectrum, and nu_e/nu_mu ratio is in progress.

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Yuichi Oyama. 2000-04-12. Current status of K2K long-baseline neutrino-oscillation experiment. https://arxiv.org/abs/hep-ex/0004015

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