Search results for "VIOLATION"
showing 10 items of 540 documents
Measurements ofCP-Violating Asymmetries and Branching Fractions inBMeson Decays toη′K
2006
We present measurements of CP-violating asymmetries and branching fractions for the decays B+->omega pi(+), B+->omega K+, and B-0 ->omega K-0. The data sample corresponds to 232x10(6) B (B) over bar pairs produced by e(+)e(-) annihilation at the Upsilon(4S) resonance. For the decay B-0 ->omega K-S(0), we measure the time-dependent CP-violation parameters S=0.51(-0.39)(+0.35)+/- 0.02, and C=-0.55(-0.26)(+0.28)+/- 0.03. We also measure the branching fractions, in units of 10(-6), B(B+->omega pi(+))=6.1 +/- 0.7 +/- 0.4, B(B+->omega K+)=6.1 +/- 0.6 +/- 0.4, and B(B-0 ->omega K-0)=6.2 +/- 1.0 +/- 0.4, and charge asymmetries A(ch)(B+->omega pi(+))=-0.01 +/- 0.10 +/- 0.01 and A(ch)(B+->omega K+)=0…
Study of decay dynamics andCPasymmetry inD+→KL0e+νedecay
2015
Using 2.92 fb(-1) of electron-positron annihilation data collected at root s = 3.773 GeV with the BESIII detector, we obtain the first measurements of the absolute branching fraction B(D+ -> K(L)(0)e(+)nu(e)) = (4.481 +/- 0.027(stat) +/- 0.103(sys))% and the CP asymmetry A(CP)(D+-> KL0e+nu e) = (-0.59 +/- 0.60(stat) +/- 1.48(sys))%. From the D+ -> K(L)(0)e(+)nu(e) differential decay rate distribution, the product of the hadronic form factor and the magnitude of the Cabibbo-Kobayashi-Maskawa matrix element, f(+)(K)(0)vertical bar V-cs vertical bar, is determined to be 0.728 +/- 0.006(stat) +/- 0.011(sys). Using vertical bar V-cs vertical bar from the SM constrained fit with the measured f(+)…
Search forB0meson decays toπ0KS0KS0,ηKS0KS0, andη′KS0KS0
2009
We describe searches for B{sup 0} meson decays to the charmless final states {pi}{sup 0}K{sub S}{sup 0}K{sub S}{sup 0}, {eta}K{sub S}{sup 0}K{sub S}{sup 0}, and {eta}{prime}K{sub S}{sup 0}K{sub S}{sup 0}. The data sample corresponds to 467 x 10{sup 6} B{bar B} pairs produced in e{sup +}e{sup -} annihilation and collected with the BABAR detector at the SLAC National Accelerator Laboratory. We find no significant signals and determine the 90% confidence level upper limits on the branching fractions, in units of 10{sup -7}, {Beta}(B{sup 0} {yields} {pi}{sup 0}K{sub S}{sup 0}K{sub S}{sup 0}) < 12, {Beta}(B{sup 0} {yields} {eta}K{sub S}{sup 0}K{sub S}{sup 0}) < 10, and {Beta}(B{sup 0} {yields} {…
Branching fractions andCP-violating asymmetries in radiativeBdecays toηKγ
2009
We present measurements of the CP-violation parameters S and C for the radiative decay B^0 → ηK^0_Sγ for B → ηKγ we also measure the branching fractions and for B^+ → ηK^+γ the time-integrated charge asymmetry A_(ch). The data, collected with the BABAR detector at the Stanford Linear Accelerator Center, represent 465 × 10^6 BB pairs produced in e^+e^- annihilation. The results are S = -0.18^(+0.49)_(-0.46) ± 0.12, C = -0.32^(+0.40)_(-0.39) ± 0.07, B(B^0 → ηK^0γ) = (7.1^(+2.1)_(-2.0) ± 0.4) × 10^(-6), B(B^+ → ηK^+γ) = (7.7 ± 1.0 ± 0.4) × 10^(-6), and A_(ch) = (-9.0^(+10.4)_(-9.8) ± 1.4) × 10^(-2). The first error quoted is statistical and the second systematic.
Search forCPviolation in the decayD±→KS0π±
2011
We report on a search for CP violation in the decay D{sup {+-}} {yields} K{sub S}{sup 0}{pi}{sup {+-}} using a data set corresponding to an integrated luminosity of 469 fb{sup -1} collected with the BABAR detector at the PEP-II asymmetric energy e{sup +}e{sup -} storage rings. The CP-violating decay rate asymmetry A{sub CP} is determined to be (-0.44 {+-} 0.13(stat) {+-} 0.10(syst))%, consistent with zero at 2.7 {sigma} and with the standard model prediction of (-0.332 {+-} 0.006)%. This is currently the most precise measurement of this parameter.
Normal and transverse single tau polarization at the Z-peak
1994
Abstract We study normal (to the collision plane) and transverse (within the collision plane) single-τ polarization in τ pairs produced in e + e − unpolarized collisions at the Z -resonance. The transverse polarization component is sensitive to the anomalous weak-magnetic moment, whereas the normal polarization component is sensitive to a CP-violating weak-electric dipole moment. We show how these components of the single τ polarization are accessible from the angular distribution of its decay products. We define a CP violating asymmetry of the τ decay products which, with 10 7 Z ′s produced, provides a sensitivity of 2.3 × 10 −18 e ·cm for the weak-electric dipole moment.
Test of CP invariance in vector-boson fusion production of the Higgs boson in the H → ττ channel in proton–proton collisions at s=13TeV with the ATLA…
2020
A test of CP invariance in Higgs boson production via vector-boson fusion is performed in the H → ττ decay channel. This test uses the Optimal Observable method and is carried out using 36.1 fb−1 of √s = 13 TeV proton–proton collision data collected by the ATLAS experiment at the LHC. Contributions from CP-violating interactions between the Higgs boson and electroweak gauge bosons are described by an effective field theory, in which the parameter ˜ d governs the strength of CP violation. No sign of CP violation is observed in the distributions of the Optimal Observable, and ˜ d is constrained to the interval [−0.090, 0.035] at the 68% confidence level (CL), compared to an expected interval …
Constraints on theWRmass andCPviolation in left-right models
1997
We update the constraints on the right-handed W{sub R} gauge boson mass, mixing angle {zeta} with the left-handed W{sub L} gauge boson, and other parameters in general left-right symmetric models with different mechanisms of CP violation. Constraints mostly independent of any assumption on the quark sector are obtained from a reanalysis of muon decay data. The best {chi}{sup 2} fit of the data gives g{sub R}/g{sub L}=0.94{plus_minus}0.09 for the ratio of right to left gauge couplings, with M{sub W{sub R}}{ge}485 GeV and {vert_bar}{zeta}{vert_bar}{le}0.0327. Fixing g{sub L}=g{sub R} (in particular for manifestly left-right symmetric models), we obtain M{sub W{sub R}}{approx_gt}549 GeV and {v…
Fully self-consistent calculations of nuclear Schiff moments
2010
We calculate the Schiff moments of the nuclei 199Hg and 211Ra in completely self-consistent odd-nucleus mean-field theory by modifying the Hartree-Fock-Bogoliubov code HFODD. We allow for arbitrary shape deformation, and include the effects of nucleon dipole moments alongside those of a CP-violating pion-exchange nucleon-nucleon interaction. The results for 199Hg differ significantly from those of previous calculations when the CP-violating interaction is of isovector character.
CP violation and limits on New Physics including recent B-s measurements
2007
We analyse present constraints on the SM parameter space and derive, in a model independent way, various bounds on New Physics contributions to $B_d^0$--$\bar B_d^0$ and $B_s^0$--$\bar B_s^0$ mixings. Our analyses include information on a large set of asymmetries, leading to the measurement of the CKM phases $\gamma$ and $\bar\beta$, as well as recent data from D0 and CDF related to the $B_s^0$--$\bar B_s^0$ system such as the measurement of $\Delta M_{B_s}$, $A_{SL}$ and $\Delta\Gamma_{s}^{CP}$. We examine in detail several observables such as the asymmetries $A_{sl}^d$, $A_{SL}$, the width differences $\Delta\Gamma_{d}$ and $\Delta\Gamma_{s}^{CP}$ and discuss the r\^ole they play in estab…