30 research outputs found
First Observation of CP Violation in B0->D(*)CP h0 Decays by a Combined Time-Dependent Analysis of BaBar and Belle Data
We report a measurement of the time-dependent CP asymmetry of B0->D(*)CP h0
decays, where the light neutral hadron h0 is a pi0, eta or omega meson, and the
neutral D meson is reconstructed in the CP eigenstates K+ K-, K0S pi0 or K0S
omega. The measurement is performed combining the final data samples collected
at the Y(4S) resonance by the BaBar and Belle experiments at the
asymmetric-energy B factories PEP-II at SLAC and KEKB at KEK, respectively. The
data samples contain ( 471 +/- 3 ) x 10^6 BB pairs recorded by the BaBar
detector and ( 772 +/- 11 ) x 10^6, BB pairs recorded by the Belle detector. We
measure the CP asymmetry parameters -eta_f S = +0.66 +/- 0.10 (stat.) +/- 0.06
(syst.) and C = -0.02 +/- 0.07 (stat.) +/- 0.03 (syst.). These results
correspond to the first observation of CP violation in B0->D(*)CP h0 decays.
The hypothesis of no mixing-induced CP violation is excluded in these decays at
the level of 5.4 standard deviations.Comment: 9 pages, 2 figures, submitted to Physical Review Letter
Measurement of in with decays by a combined time-dependent Dalitz plot analysis of BaBar and Belle data
We report measurements of and from a
time-dependent Dalitz plot analysis of with decays, where the light unflavored and neutral
hadron is a , , or meson. The analysis is
performed with a combination of the final data sets of the \babar\ and Belle
experiments containing and
pairs collected at the resonance at the
asymmetric-energy B factories PEP-II at SLAC and KEKB at KEK, respectively. We
measure and . The result for the direct
measurement of the angle is . The last quoted
uncertainties are due to the composition of the decay amplitude model, which is newly established by a Dalitz plot
amplitude analysis of a high-statistics data sample
as part of this analysis. We find the first evidence for at the
level of standard deviations. The measurement excludes the trigonometric
multifold solution at the level of
standard deviations and therefore resolves an ambiguity in the
determination of the apex of the CKM Unitarity Triangle. The hypothesis of
is ruled out at the level of standard deviations, and
thus CP violation is observed in decays.Comment: To be submitted to Physical Review
The Physics of the B Factories
This work is on the Physics of the B Factories. Part A of this book contains a brief description of the SLAC and KEK B Factories as well as their detectors, BaBar and Belle, and data taking related issues. Part B discusses tools and methods used by the experiments in order to obtain results. The results themselves can be found in Part C
The Belle II Physics Book
We present the physics program of the Belle II experiment, located on the
intensity frontier SuperKEKB collider. Belle II collected its first
collisions in 2018, and is expected to operate for the next decade. It is
anticipated to collect 50/ab of collision data over its lifetime. This book is
the outcome of a joint effort of Belle II collaborators and theorists through
the Belle II theory interface platform (B2TiP), an effort that commenced in
2014. The aim of B2TiP was to elucidate the potential impacts of the Belle II
program, which includes a wide scope of physics topics: B physics, charm, tau,
quarkonium, electroweak precision measurements and dark sector searches. It is
composed of nine working groups (WGs), which are coordinated by teams of
theorist and experimentalists conveners: Semileptonic and leptonic B decays,
Radiative and Electroweak penguins, phi_1 and phi_2 (time-dependent CP
violation) measurements, phi_3 measurements, Charmless hadronic B decay, Charm,
Quarkonium(like), tau and low-multiplicity processes, new physics and global
fit analyses. This book highlights "golden- and silver-channels", i.e. those
that would have the highest potential impact in the field. Theorists
scrutinised the role of those measurements and estimated the respective
theoretical uncertainties, achievable now as well as prospects for the future.
Experimentalists investigated the expected improvements with the large dataset
expected from Belle II, taking into account improved performance from the
upgraded detector.Comment: 689 page
Justification of the choice of composite material for the restoration of teeth after endodontic treatment
Relevance. The forecast of the functionality of the tooth after endodontic treatment, when resistance to mechanical loads is significantly reduced, depends on the choice of method and material for the restoration.Aim. The aim of the work was to compare the physicomechanical and clinical qualities of composite materials used to restore posterior teeth after endodontic treatment.Materials and methods. Studies were carried out according to GOST 31574-2012 – determination of the curing depth, strength with diametral rupture, bending and determination of water absorption and water solubility, as well as the integrity of the restorations, the presence of chips, the development of secondary caries after 24 months.Result of research. Based on a comparison of the physicomechanical and clinical qualities of the composite materials Tetric EvoCeram (Ivoclar Vivadent) and SDR (Dentsply) used to restore the posterior teeth after endodontic treatment, as well as the timing of the time spent on treatment, the choice of a composite material for the restoration is justified.Conclusions. Indicators for all the parameters studied composite materials Tetric EvoCeram and SDR more perfect than required by GOST. The time spent on the restoration of the posterior teeth using a two-layer technique using the composite SDR as the basis and restoring the occlusal surface with the Tetric EvoCeram composite is significantly on average 10 minutes less than with a tooth restoration using the multilayer Tetric EvoCeram composite material ( p ≤ 0.05)