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The stress field due to olivine‐spinel phase transition in and around a descending plate is studied based on the calculations for an equilibrium phase transition with a constant Clapeyron's slope and for a nonequilibrium transition taking a kinetic effect into consideration. The material concerned is assumed to be a viscoelastic body whose physical coefficients are functions of temperature and pressures. The calculated stress distribution for the equilibrium transition is characterized by a compressional stress near the upper and/or lower surfaces of the plate and by a tensional stress at the central part in the depth range from 200 to 550 km, the magnitude of principal stress being greater than 0.5 GPa. However, for the nonequilibrium transition a tensional stress predominates near the upper and lower surfaces, and the central part is compressional in the depth range from 300 to 600 km, unlike the case of equilibrium transition. The maximum principal stress in the latter case is greater than 2 GPa, which is much more than that for the equilibrium transition. The principal axes in the high stressed region are oriented almost parallel to the descending direction in both cases. Comparison of the calculated results to the actually observed seismicity‐depth relation and to focal mechanisms of deep focus earthquakes in descending plates beneath island arcs shows that the nonequilibrium phase transition agrees better with the observations.

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The suppressed decay chain B(-)→DK(-), D→K(+)π(-), where D indicates a D(¯)(0) or D(0) state, provides important information on the CP-violating angle ϕ(3). We measure the ratio R(DK) of the decay rates to the favored mode B(-)→DK(-), D→K(-)π(+) to be R(DK)=[1.63(-0.41)(+0.44)(stat)(-0.13)(+0.07)(syst)]×10(-2), which indicates the first evidence of the signal with a significance of 4.1σ. We also measure the asymmetry A(DK) between the charge-conjugate decays to be A(DK)=-0.39(-0.28)(+0.26)(stat)(-0.03)(+0.04)(syst). The results are based on the full 772×10(6) BB(¯) pair data sample collected at the Υ(4S) resonance with the Belle detector.

Recent seismic studies using a high-gain seismograph network have demonstrated the existence of a double-planed seismic zone in the descending plate beneath island arcs such as northeastern Japan, Kurile, and Central Aleutian. Several hypotheses in terms of plate unbending, phase changes, mechanical models have been proposed to explain the characteristic features of the doubleplaned structure. This paper presents a new hypothesis that thermal stress due to non-uniform temperature distribution in the descending plate is the main causative force for genesis of earthquakes in the double-planed seismic zone.Based on the estimated temperature distribution in the plate with a dip