Measurement of CP asymmetries in B0→K0π0 decays

We report measurements of CP violation parameters in B0→K0π0 decays based on a data sample of 657×106BB̄ pairs collected with the Belle detector at the KEKB e+e- asymmetric-energy collider. We use B0→KS0π0 decays for both mixing-induced and direct CP violating asymmetry measurements and B0→KL0π0 decays for the direct CP violation measurement. The CP violation parameters obtained are sin 2 1eff=+0.67±0. 31(stat)±0.08(syst) and AK0π0=+0.14±0.13(stat)±0. 06(syst). The branching fraction of B0→K0π0 decay is measured to be B(B0→K0π0)=(8.7±0.5(stat.)±0.6(syst.))×10 -6. The observed AK0π0 value differs by 1.9 standard deviations from the value expected from an isospin sum rule. © 2010 The American Physical Society.

À propos de ce résultat

Cette page est générée automatiquement et peut contenir des informations qui ne sont pas correctes, complètes, à jour ou pertinentes par rapport à votre recherche. Il en va de même pour toutes les autres pages de ce site. Veillez à vérifier les informations auprès des sources officielles de l'EPFL.

Concepts associés

Chargement

Publications associées

Chargement

Tagir Aushev, Vladislav Balagura, Sun Hee Kim, Jing Li, Remi Léandre Albert Louvot, Olivier Schneider
2010
Article

Résumé

Official source

https://infoscience.epfl.ch/record/154244?ln=fr

À propos de ce résultat

Concepts associés (8)

Concepts associés

Chargement

Publications associées (119)

Publications associées

Chargement

Rapport de branchement

En physique des particules et en physique nucléaire, le rapport de branchement (ou rapport d'embranchement) désigne la probabilité de voir un nucléide emprunter un mode de désintégration radioactive d

Violation de CP

En physique des particules, la violation de CP est une violation de la symétrie CP, c'est-à-dire de la combinaison de la symétrie C (symétrie de conjugaison de charge) et de la symétrie P (symétrie de

Mesure physique

La mesure physique est l'action de déterminer la ou les valeurs d'une grandeur (longueur, capacité), par comparaison avec une grandeur constante de même espèce prise comme terme de référence (étalon

Evidence for Direct CP Violation in B-+/- -> eta h(+/-) and Observation of B-0 -> eta K-0

Tagir Aushev, Ji Hyun Kim, Jing Li, Zhen Liu, Remi Léandre Albert Louvot, Olivier Schneider, Mingkui Wang

We report measurements of the branching fractions and CP asymmetries for B-+/- -> eta h(+/-) (h = K or pi) and the observation of the decay B-0 -> eta K-0 from the final data sample of 772 x 10(6) B (B) over bar pairs collected with the Belle detector at the KEKB asymmetric-energy e(+)e(-) collider. The measured branching fractions are B(B-+/- -> eta K-+/-) = (2.12 +/- 0.23 +/- 0.11) x 10(-6), B(B-+/- -> eta pi(+/-)) = (4.07 +/- 0.26 +/- 0.21) x 10(-6), and B(B-0 -> eta K-0) = (1.27(-0.29)(+0.33) +/- 0.08) x 10(-6), where the last decay is observed for the first time with a significance of 5.4 standard deviations (sigma). We also find evidence for CP violation in the charged B modes, A(CP)(B-+/- -> eta K-+/-) = -0.38 +/- 0.11 +/- 0.01 and A(CP)(B-+/- -> eta pi(+/-)) = -0.19 +/- 0.06 +/- 0.01 with significances of 3.8 sigma and 3.0 sigma, respectively. For all measurements, the first and second uncertainties are statistical and systematic, respectively.

2012

Chargement

Evidence for D0-D̄0 mixing

Tagir Aushev, Vladislav Balagura, Aurelio Bay, Stewart Cole, Sun Hee Kim, Jing Li, Olivier Schneider, Mingkui Wang, Jean Wicht, Yuan Yuan, Lei Zhang

We observe evidence for D0-D̄0 mixing by measuring the difference in the apparent lifetime when a D0 meson decays to the CP eigenstates K+K- and π+π- and when it decays to the final state K-π+. We find the relative difference of the lifetimes yCP to be [1.31±0.32(stat)±0.25(syst)] %, 3.2 standard deviations from zero. We also search for a CP asymmetry between D0 and D̄0 decays; no evidence for CP violation is found. These results are based on 540fb-1 of data recorded by the Belle detector at the KEKB e+e- collider. © 2007 The American Physical Society.

2007

Chargement

Time-dependent CP-violating asymmetries in b→sq q transitions

Tagir Aushev, Aurelio Bay, Sun Hee Kim, Sanjeev Kumar, Jing Li, Olivier Schneider, Mingkui Wang, Lei Zhang

We present new measurements of CP-violation parameters in B0→K0, K+K-KS0, f0(980)KS0, η′KS0, ωKS0, and KS0π0 decays based on a sample of 275×106 BB̄ pairs collected at the Υ(4S) resonance with the Belle detector at the KEKB energy-asymmetric e+e- collider. One neutral B meson is fully reconstructed in one of the specified decay channels, and the flavor of the accompanying B meson is identified from its decay products. CP-violation parameters for each of the decay modes are obtained from the asymmetries in the distributions of the proper-time intervals between the two B decays. The combined result for the B0→K0, K+K-KS0, f0(980)KS0, η′KS0, ωKS0, KS0π0, and previously reported KS0KS0KS0 decays differs from the SM expectation by 2.4 standard deviations. © 2005 The American Physical Society.

2005

Chargement