scholarly journals FIRST MEASUREMENT OF THE CP-VIOLATING ASYMMETRIES WITH BABAR

2001 ◽  
Vol 16 (supp01b) ◽  
pp. 611-615
Author(s):  
◽  
YURY G. KOLOMENSKY
Keyword(s):  
Maximum Likelihood ◽  
B Mesons ◽  
Time Distribution ◽  
B Meson ◽  
The Other ◽  
Time Dependent ◽  
Preliminary Measurement ◽  
Neutral B Meson ◽  
Asymmetry Amplitude ◽  
Babar Detector

We report on a preliminary measurement of time-dependent CP-violating asymmetries in [Formula: see text] and [Formula: see text] decays recorded by the BABAR detector at the PEP-II asymmetric B Factory at SLAC. The data sample consisted of 9.0 fb-1 collected at the ϒ(4S) resonance and 0.8 fb-1 off-resonance. One of the pair of neutral B mesons produced at the ϒ(4S) was fully reconstructed, while the flavor of the other neutral B meson was tegged at the time of its decay. The value of the asymmetry amplitude, sin 2β, was determined from a maximum likelihood fit to the time distribution of 120 tegged candidates to be sin 2β=0.12±0.37( stat. )± 0.09( syst. ) (preliminary).

Measurement of CP-Violating Asymmetries in B0 → (ρπ)0 Using a Time-Dependent Dalitz Plot Analysis

2005 ◽  
Vol 20 (15) ◽  
pp. 3551-3553
Author(s):  
◽  
ATTILA MIHALYI
Keyword(s):  
Form Factor ◽  
Maximum Likelihood ◽  
Decay Rate ◽  
Bilinear Form ◽  
Dalitz Plot ◽  
Time Dependent ◽  
Preliminary Measurement ◽  
Plot Analysis ◽  
B Factory ◽  
Babar Detector

We present the preliminary measurement of CP-violating asymmetries in B0 → (ρπ)0 → π+π-π0 decays using a time-dependent Dalitz plot analysis. The results are obtained from a data sample of 213 million [Formula: see text] decays, collected by the BaBar detector at the PEPII asymmetric-energy B -Factory at SLAC. We measure 16 coefficients of the bilinear form factor terms occurring in the time-dependent decay rate of the B0 meson with the use of a maximum-likelihood fit. The physically relevant CP parameters are derived from these coefficients.

MEASUREMENT OF CP ASYMMETRY IN $B^0 \to f_0 K^0_S$, B0 → ϕK0 AND $B^0 \to K^+K^-K^0_S$ DECAYS

2005 ◽  
Vol 20 (15) ◽  
pp. 3531-3534
Author(s):  
◽  
PAUL E. KUTTER
Keyword(s):  
Maximum Likelihood ◽  
Cp Violation ◽  
B Meson ◽  
Time Dependent ◽  
Final States ◽  
Cp Asymmetry ◽  
Meson Factory ◽  
Babar Detector ◽  
Cp Asymmetries

We present results on time-dependent CP asymmetries in [Formula: see text] and B0 → K+K-K0. The measurements use a data sample consisting of approximately [Formula: see text] and 227(B0 → K+K-K0) million B-meson pairs recorded at the ϒ(4S) resonance with the BABAR detector at the PEP-II B-meson Factory at SLAC. From a time-dependent maximum likelihood fit, we measure for [Formula: see text]: the mixing-induced CP violation parameter [Formula: see text] and the direct CP violation parameter Cf0K = -0.24 ± 0.31 ( stat ) ± 0.15 ( syst ). From a simultaneous fit to [Formula: see text] and [Formula: see text] decays, we find: [Formula: see text] and CϕK = 0.00 ± 0.23 ( stat ) ± 0.05 ( syst ). For [Formula: see text] decays with [Formula: see text] decays excluded, we find: [Formula: see text] and [Formula: see text]. From the [Formula: see text] decays with [Formula: see text] decays excluded, we extract the fraction of CP-even final states from angular moments feven = 0.89 ± 0.08 ± 0.06.

scholarly journals A STUDY OF $B^0\bar B^0$ OSCILLATIONS WITH FULLY RECONSTRUCTED B MESONS WITH THE BABAR DETECTOR

2001 ◽  
Vol 16 (supp01a) ◽  
pp. 407-409
Author(s):  
◽  
SHAHRAM RAHATLOU
Keyword(s):  
B Mesons ◽  
Center Of Mass ◽  
Time Dependent ◽  
Flavor Oscillations ◽  
Babar Detector

Time-dependent [Formula: see text] flavor oscillations are studied in e+e- annihilation data collected with the BABAR detector at center-of-mass energies near the ϒ(4S) resonance. We report a preliminary result for the time-dependent [Formula: see text] oscillations frequency, Δmd=0.512±0.017±0.022 ℏ ps -1.

CP-ASYMMETRIES IN NEUTRAL B-MESON DECAYS IN A CLASS OF LEFT-RIGHT SYMMETRIC MODELS

1996 ◽  
Vol 11 (04) ◽  
pp. 299-306
Author(s):  
W.K. SZE ◽  
HERNG YAO
Keyword(s):  
Standard Model ◽  
B Mesons ◽  
B Meson ◽  
Standard Model Prediction ◽  
Boson Mass ◽  
Neutral B Meson ◽  
The Standard Model ◽  
Mixing Matrix ◽  
Gauge Boson Mass ◽  
Cp Asymmetries

In left-right symmetric models with a general right-handed quark mixing matrix VR, CP-asymmetries of neutral B-mesons can deviate appreciably from the standard model prediction. By assuming a Gronau-Wakaizumi (GW) form of VR, we calculate asymmetries of B0 decays to two-body CP-eigenstates for various possible right-handed gauge boson mass MR. It is found that these CP-asymmetries show a sharp transition from the GW results to the standard model ones in the neighborhood of MR≃800 GeV .

$B^0_{d,s}-\bar{B}^0_{d,s}$ MIXING IN THE MODEL III 2HDM

2005 ◽  
Vol 20 (01) ◽  
pp. 161-174 ◽  
Author(s):  
CHAO-SHANG HUANG ◽  
JIAN-TAO LI
Keyword(s):  
B Meson ◽  
New Physics ◽  
Mass Splitting ◽  
High Accuracy ◽  
Time Dependent ◽  
Meson Mass ◽  
Leading Order ◽  
Cp Asymmetry ◽  
Neutral B Meson ◽  
Accuracy Data

In the model III 2HDM there are new CP violating phases which would affect the [Formula: see text] mixing. In this paper, we calculate the new physics contributions to the neutral B meson mass splitting ΔMBq (q=d,s) at the next-to-leading order (NLO) level. Using the high accuracy data and other relevant data, we draw the constraints on the parameter space of the model III 2HDM. Moreover, we calculate the new physics corrections to the ratio q/p. It is found that the phase of (q/p)n for Bd which is due to the new contributions is very small and consequently in agreement with the measurements of the time dependent CP asymmetry SJ/ψK in B→J/ψKS. On the contrary, the phase of (q/p)n for Bs is large enough to give significant effects on CP violation in the neutral Bs system.

scholarly journals First Measurement of the Branching Fraction of $e^+ e^- \to B^0 \overline{B}^0$

2005 ◽  
Vol 20 (16) ◽  
pp. 3605-3608
Author(s):  
◽  
Romulus Godang
Keyword(s):  
B Meson ◽  
Branching Fraction ◽  
Branching Fractions ◽  
Partial Reconstruction ◽  
Neutral B Meson ◽  
Signal Decay ◽  
Soft Pion ◽  
Using Data ◽  
The Individual ◽  
Babar Detector

We report the first measurement of the absolute branching fraction [Formula: see text] at the ϒ(4S) resonance using data collected with the BABAR detector at the PEP-II asymmetric-energy e+e- storage ring. The analysis is performed with partial reconstruction of the decay [Formula: see text], where the presence of a signal decay is determined using only the lepton and the soft pion from the D* decay. By reconstructing events with one or two signal decays, we obtain a preliminary result of [Formula: see text]. Our result does not depend on branching fractions of the [Formula: see text] and the D*+ decays, on the individual simulated reconstruction efficiencies, on the ratio of the charged and neutral B meson lifetimes, or on the assumption of isospin symmetry.

Improved measurement of CP-violation in $B \to (c{\bar c})K^{(\ast)0}$ decays

2005 ◽  
Vol 20 (15) ◽  
pp. 3522-3526
Author(s):  
◽  
David J. Lange
Keyword(s):  
B Meson ◽  
B Decays ◽  
Final State ◽  
Cp Asymmetry ◽  
Neutral B Meson ◽  
Decay Products ◽  
The Standard Model ◽  
Using Data ◽  
Babar Detector ◽  
Neutral B Decays

We present results on time-dependent CP asymmetries in neutral B decays. The amplitude of the CP asymmetry, sin 2β in the Standard Model, is derived from decay-time distributions from events in which one neutral B meson is fully reconstructed in a final state containing a charmonium meson and the other B meson is determined to be either a B0or [Formula: see text] from its decay products. Using data collected by the BABAR detector at the PEP-II asymmetric-energy B Factory at SLAC, we measure sin 2β = 0.722 ± 0.040( stat ) ± 0.023( syst ) and [Formula: see text], determining the sign of cos 2β to be positive at 86% CL.

scholarly journals Radiative Penguin Decays of B Mesons: Measurements of B → K*γ, $B \to K^*_2(1430)\gamma$, and Search for B0 → ϕγ

2005 ◽  
Vol 20 (16) ◽  
pp. 3621-3623
Author(s):  
◽  
Johannes M. Bauer
Keyword(s):  
Standard Model ◽  
B Mesons ◽  
B Meson ◽  
Branching Fractions ◽  
Decay Rates ◽  
Isospin Asymmetry ◽  
Penguin Decays ◽  
B Factory ◽  
Babar Detector

Electromagnetic radiative penguin decays of the B meson were studied with the BABAR detector at SLAC's PEP-II asymmetric-energy B Factory. Branching fractions and isospin asymmetry of the decay B → K*γ, branching fractions of [Formula: see text], and a search for B0 → ϕγ are presented. The decay rates may be enhanced by contributions from non-standard model processes.

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