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A new result for the transverse mu^+ polarization, P_T, in the decay K^+ --> pi^0 mu^+ nu has been obtained in the KEK E246 experiment. Combined with our earlier result, P_T = (-1.12 +- 2.17(stat) +- 0.90(syst))x10^{-3} and Im(\xi) = (-0.28 +- 0.69(stat) +- 0.30(syst))x10^{-2}, which are consistent with no T-violation., Comment: 5 pages, 2 figures, to be published in the Proceedings of the PANIC02, Osaka, Sept 30 - Oct 4, 2002

Hyperon-proton scattering is being studied at KEK in order to obtain a better understanding standing of the baryon-baryon interaction. A scintilating fiber (SCIFI) block detector has been used as a production target of hyperons as well as a target for hyperon scattering on hydrogen. The pilot experiment (E251) for Σ + p scattering has been completed, and the next experiment (E289) for Σ + p, Σ − p and Λp channels has finished its data taking and is now uder analysis.

The new low energy hyperon‐nucleon scattering data have been long waited since the low statistics data were obtained in 1960s from the bubble chamber experiments. At KEK, an experiment to measure ∑++p elastic scattering has been performed utilizing the novel scintillating fiber technology. In this report we present the status of the analysis on this experiment and the preliminary total cross section data of ∑++p scattering.

Energy spectra of charged particles produced by electron and bremsstrahlung bombardment of 6Li and 7Li were measured by means of a magnetic spectrometer and solid-state detectors. Assuming that all transitions leave the residual nucleus in the ground state, the photonuclear cross sections were obtained using both bremsstrahlung and E1 virtual photon spectra. Comparison of the present real and virtual photon results is made with those of previous experiments.

The results of measurements on the 3He(e,e′d)1H reaction are presented. No evidence for structure in 3He has been observed over the energy region 16–27 MeV.

The electrodisintegration cross sections, 16O(e,α0)12C,e′ and 20Ne(e,α0)16O,e′, have been measured and, by using virtual photon analysis, a comparison with photodisintegration experiments has been made. Satisfactory agreement with earlier 12C(α,γ0)16O experiments was found and the 20Ne(γ,α0)16O reaction reveals several pronounced resonances.

Tritons resulting from the electrodisintegration of 7Li have been measured at 90° for an incident electron energy of 23.8 MeV over an energy range which ensured that only tritons emitted in the two-body channel were detected. The electrodisintegration cross sections were converted to equivalent photodisintegration data and compared to earlier results. Large discrepancies are observed. It is found that the (γ,3H) channel contributes appreciably to the electric dipole sum rule for 7Li.