Byeong-Geun Cheon

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We present a measurement of the standard model CP violation parameter sin2 phi(1) based on a 29.1 fb(-1) data sample collected at the Upsilon(4S) resonance with the Belle detector at the KEKB asymmetric-energy e(+)e(-) collider. One neutral B meson is fully reconstructed as a J/psi K(S), psi(2S)K(S), chi(c1)K(S), eta(c)K(S), J/psi K(L), or J/psi K(*0) decay(More)
We observe evidence for D(0)-D(0) mixing by measuring the difference in the apparent lifetime when a D(0) meson decays to the CP eigenstates K(+)K(-) and pi(+)pi(-) and when it decays to the final state K(-)pi(+). We find the relative difference of the lifetimes y(CP) to be [1.31+/-0.32(stat)+/-0.25(syst)]%, 3.2 standard deviations from zero. We also search(More)
We report the first observation of the B-->Dmacr;D(sJ)(2317) and B-->Dmacr;D(sJ)(2457) decays based on 123.8x10(6) BBmacr; events collected with the Belle detector at KEKB. We observe the D(sJ)(2317) decay to D(s)pi(0) and the D(sJ)(2457) decay to the D(*)(s)pi(0) and D(s)gamma final states. We also set 90% C.L. upper limits for the decays(More)
We perform a full amplitude analysis of B 0 ! c 0 K þ À decays, with c 0 ! þ À or e þ e À , to constrain the spin and parity of the Zð4430Þ À. The J P ¼ 1 þ hypothesis is favored over the 0 À , 1 À , 2 À and 2 þ hypotheses at the levels of 3:4, 3:7, 4:7 and 5:1, respectively. The analysis is based on a 711 fb À1 data sample that contains 772 Â 10 6 B " B(More)
The neutral B meson pair produced at the Upsilon(4S) should exhibit a nonlocal correlation of the type discussed by Einstein, Podolsky, and Rosen. We measure this correlation using the time-dependent flavor asymmetry of semileptonic B(0) decays, which we compare with predictions from quantum mechanics and two local realistic models. The data are consistent(More)
We present a measurement of angular observables and a test of lepton flavor universality in the B→K^{*}ℓ^{+}ℓ^{-} decay, where ℓ is either e or μ. The analysis is performed on a data sample corresponding to an integrated luminosity of 711  fb^{-1} containing 772×10^{6} BB[over ¯] pairs, collected at the ϒ(4S) resonance with the Belle detector at the(More)
We observe evidence for CP violation in the decay D+ → K(S)(0)π+ using a data sample with an integrated luminosity of 977  fb(-1) collected by the Belle detector at the KEKB e+ e- asymmetric-energy collider. The CP asymmetry in the decay is measured to be (-0.363±0.094±0.067)%, which is 3.2 standard deviations away from zero, and is consistent with the(More)