0000000000204618
AUTHOR
N. Tamura
Measurement of single spin asymmetry in η-meson production in p↑p and p̄↑p interactions in the beam fragmentation region at 200 GeV/c
We present experimental results on measuring a single spin asymmetry in η-meson production in the interaction of transversely polarized protons and antiprotons at plab = 200 GeV/c with a proton target in the region 0.2 < xF < 0.7 for p↑p, 0.3 < xF < 0.7 for p↑p and 0.7 < pT < 2.0 GeV/c. A comparison of single spin asymmetries in π- and η-meson production is made.
Evidence for Muon Neutrino Oscillation in an Accelerator-Based Experiment
We present results for muon neutrino oscillation in the KEK to Kamioka (K2K) long-baseline neutrino oscillation experiment. K2K uses an accelerator-produced muon neutrino beam with a mean energy of 1.3 GeV directed at the Super-Kamiokande detector. We observed the energy dependent disappearance of muon neutrino, which we presume have oscillated to tau neutrino. The probability that we would observe these results if there is no neutrino oscillation is 0.0050% (4.0 sigma).
Measurement of neutrino oscillation by the K2K experiment
We present measurements of nu_mu disappearance in K2K, the KEK to Kamioka long-baseline neutrino oscillation experiment. One hundred and twelve beam-originated neutrino events are observed in the fiducial volume of Super-Kamiokande with an expectation of 158.1^{+9.2}_{-8.6} events without oscillation. A distortion of the energy spectrum is also seen in 58 single-ring muon-like events with reconstructed energies. The probability that the observations are explained by the expectation for no neutrino oscillation is 0.0015% (4.3sigma). In a two flavor oscillation scenario, the allowed Delta m^2 region at sin^2(2theta) is between 1.9 and 3.5 x 10^{-3} eV^2 at the 90% C.L. with a best-fit value o…
Performance of the ATLAS silicon strip detector modules
Abstract The performance of the silicon strip detector prototypes developed for use in ATLAS at the LHC is reported. Baseline detector assemblies (“modules”) of 12 cm length were read out with binary electronics at 40 MHz clock speed. For both irradiated and unirradiated modules, the tracking efficiency, noise occupancy, and position resolution were measured as a function of bias voltage, binary hit threshold, and detector rotation angle in a 1.56 T magnetic field. Measurements were also performed at a particle flux comparable to the one expected at the LHC.
Beam test of the ATLAS silicon detector modules
Abstract Results are reported from a beam test of prototype silicon microstrip detectors and front-end electronics developed for use in the LHC detector ATLAS. The detector assemblies (“modules”) were 12 cm long and were read out with binary electronics. Both irradiated and unirradiated modules were measured in a 1.56 T magnetic field for efficiency, noise occupancy, and position resolution as a function of bias voltage, binary hit threshold, and detector rotation angle with respect to the beam direction.
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.
Measurement of inclusive pi(0) production in the charged-current interactions of neutrinos in a 1.3-GeV wide band beam
In this paper we report on the measurement of the rate of inclusive $\pi^0$ production induced by charged-current neutrino interactions in a C$_8$H$_8$ target at a mean energy of 1.3 GeV in the K2K near detector. Out of a sample of 11,606 charged current neutrino interactions, we select 479 $\pi^0$ events with two reconstructed photons. We find that the cross section for the inclusive $\pi^0$ production relative to the charged-current quasi-elastic cross section is $$\frac{\sigma_{CC\pi^0}}{\sigma_{CCQE}}=0.426\pm0.032(stat.)\pm0.035(syst.)$$ The energy dependent cross section ratio is also measured. The results are consistent with previous experiments for exclusive channels on different ta…