arXiv subjects

K2K collaboration

Publications and source records attributed to K2K collaboration.

3 recordsLinked to original sources

arXiv2006

Improved search for $ν_μ\to ν_e$ oscillation in a long-baseline accelerator experiment

We performed an improved search for $ν_μ\to ν_e$ oscillation with the KEK to Kamioka (K2K) long-baseline neutrino oscillation experiment, using the full data sample of $9.2 \times 10^{19}$\xspace protons on target. No evidence for a $ν_e$ appearance signal was found, and we set bounds on the $ν_μ\to ν_e$ oscillation parameters. At $Δm^2$ = $2.8 \times 10^{-3} \mathrm{eV}^2$, the best fit value of the K2K $ν_μ$ disappearance analysis, we set an upper limit of $\sin^2 2θ_{μe}$ $<$ 0.13 at 90% confidence level.

hep-ex↗

arXiv2005

Search for coherent charged pion production in neutrino-carbon interactions

We report the result from a search for charged-current coherent pion production induced by muon neutrinos with a mean energy of 1.3 GeV. The data are collected with a fully active scintillator detector in the K2K long-baseline neutrino oscillation experiment. No evidence for coherent pion production is observed and an upper limit of $0.60 \times 10^{-2}$ is set on the cross section ratio of coherent pion production to the total charged-current interaction at 90% confidence level. This is the first experimental limit for coherent charged pion production in the energy region of a few GeV.

hep-ex↗

arXiv2000

Design, construction, and operation of SciFi tracking detector for K2K experiment

We describe the construction and performance of a scintillating fiber detector used in the near detector for the K2K (KEK to Kamioka, KEK E362) long baseline neutrino oscillation experiment. The detector uses 3.7 m long and 0.692 mm diameter scintillating fiber coupled to image-intensifier tubes (IIT), and a CCD camera readout system. Fiber sheet production and detector construction began in 1997, and the detector was commissioned in March, 1999. Results from the first K2K runs confirm good initial performance : position resolution is estimated to be about 0.8 mm, and track finding efficiency is $98 \pm 2$ % for long tracks (i.e., those which intersect more than 5 fiber planes). The hit efficiency was estimated to be $92 \pm 2$ % using cosmic-ray muons, after noise reduction at the offline stage. The possibility of using the detector for particle identification is also discussed.

hep-ex↗