학술논문
Measurement of cos2β in B0 →d (∗)h0 with D → KS0 π+π- decays by a combined time-dependent Dalitz plot analysis of B a B ar and Belle data
Document Type
article
Author
Adachi, I; Adye, T; Ahmed, H; Ahn, JK; Aihara, H; Akar, S; Alam, MS; Albert, J; Anulli, F; Arnaud, N; Asner, DM; Aston, D; Atmacan, H; Aushev, T; Ayad, R; Badhrees, I; Bakich, AM; Banerjee, S; Bansal, V; Barlow, RJ; Batignani, G; Beaulieu, A; Behera, P; Bellis, M; Ben-Haim, E; Bernard, D; Bernlochner, FU; Bettarini, S; Bettoni, D; Bevan, AJ; Bhardwaj, V; Bhuyan, B; Bianchi, F; Biasini, M; Biswal, J; Blinov, VE; Bomben, M; Bondar, A; Bonneaud, GR; Bozek, A; Bozzi, C; Bračko, M; Browder, TE; Brown, DN; Bünger, C; Burchat, PR; Buzykaev, AR; Calabrese, R; Calcaterra, A; Calderini, G; Di Carlo, S; Carpinelli, M; Cartaro, C; Casarosa, G; Cenci, R; Chao, DS; Chauveau, J; Cheaib, R; Chen, A; Chen, C; Cheng, CH; Cheon, BG; Chilikin, K; Cho, K; Choi, Y; Choudhury, S; Chrzaszcz, M; Cibinetto, G; Cinabro, D; Cochran, J; Coleman, JP; Convery, MR; Cowan, G; Cowan, R; Cremaldi, L; Cunliffe, S; Dash, N; Davier, M; Davis, CL; De Mori, F; De Nardo, G; Denig, AG; De Sangro, R; Dey, B; Di Lodovico, F; Dittrich, S; DoleŽal, Z; Dorfan, J; Drásal, Z; Druzhinin, VP; Dunwoodie, W; Ebert, M; Echenard, B; Eidelman, S; Eigen, G; Eisner, AM; Emery, S; Epifanov, D; Ernst, JA
Source
Physical Review D. 98(11)
Subject
Language
Abstract
We report measurements of sin2β and cos2β using a time-dependent Dalitz plot analysis of B0→D(∗)h0 with D→KS0π+π- decays, where the light unflavored and neutral hadron h0 is a π0, η, or ω meson. The analysis uses a combination of the final data sets of the BaBar and Belle experiments containing 471×106 and 772×106 BB pairs collected at the (4S) resonance at the asymmetric-energy B factories PEP-II at SLAC and KEKB at KEK, respectively. We measure sin2β=0.80±0.14(stat)±0.06(syst)±0.03(model) and cos2β=0.91±0.22(stat)±0.09(syst)±0.07(model). The result for the direct measurement of the angle is β=(22.5±4.4(stat)±1.2(syst)±0.6(model))°. The last quoted uncertainties are due to the composition of the D0→KS0π+π- decay amplitude model, which is newly established by a Dalitz plot amplitude analysis of a high-statistics e+e-→cc data sample as part of this analysis. We find the first evidence for cos2β>0 at the level of 3.7 standard deviations. The measurement excludes the trigonometric multifold solution π/2-β=(68.1±0.7)° at the level of 7.3 standard deviations and therefore resolves an ambiguity in the determination of the apex of the CKM Unitarity Triangle. The hypothesis of β=0° is ruled out at the level of 5.1 standard deviations, and thus CP violation is observed in B0→D(∗)h0 decays. The measurement assumes no direct CP violation in B0→D(∗)h0 decays.