Search results for "WEAK-INTERACTIONS"

showing 3 items of 3 documents

Nuclear anapole moment interaction in BaF from relativistic coupled-cluster theory

2018

We present high accuracy relativistic coupled cluster calculations of the P-odd interaction coefficient $W_A$ describing the nuclear anapole moment effect on the molecular electronic structure. The molecule under study, BaF, is considered a promising candidate for the measurement of the nuclear anapole moment, and the preparation for the experiment is now underway [Altunas et al., Phys. Rev. Lett. 120, 142501 (2018)]. Influence of various computational parameters (size of the basis set, treatment of relativistic effects, and treatment of electron correlation) on the calculated $W_A$ coefficient is investigated and a recommended value of 147.7 Hz with an estimated uncertainty of 1.5% is prop…

ATOMIC PARITY NONCONSERVATIONDIATOMIC-MOLECULESP-ODDVIOLATIONAtomic Physics (physics.atom-ph)Nuclear TheoryDENSITY FUNCTIONALSFOS: Physical sciences01 natural sciences010305 fluids & plasmasPhysics - Atomic PhysicsENHANCEMENTMolecular electronic structure0103 physical sciencesIMPLEMENTATIONNuclear Experiment010306 general physicsBasis setPhysicsElectronic correlationELECTRIC-FIELD GRADIENTSDiatomic moleculeWEAK-INTERACTIONSCoupled clusterMoment (physics)Atomic physicsRelativistic quantum chemistryAPPROXIMATIONPhysical Review A
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A study of the Lorentz structure in tau decays

2000

This paper describes a measurement of the Michel parameters, \eta, \rho, \xi, \xi\delta, and the average \nu_{\tau} helicity, h_{\nu_{\tau}}, in tau lepton decays together with the first measurement of the tensor coupling in the weak charged current. The tau+tau- pairs were produced at the LEP e+e- collider at CERN from 1992 through 1995 in the DELPHI detector. Assuming lepton universality in the decays of the tau the measured values of the parameters were: \eta = -0.005 +/- 0.036 +/- 0.037, \rho = 0.775 +/- 0.023 +/- 0.020, \xi = 0.929 +/- 0.070 +/- 0.030, \xi\delta = 0.779 +/- 0.070 +/- 0.028, h_{\nu_{\tau}} = -0.997 +/- 0.027 +/- 0.011. The strength of the tensor coupling was measured to…

Particle physicsPhysics and Astronomy (miscellaneous)CHARGED WEAK-INTERACTIONSLUND MONTE-CARLOENERGIESLorentz transformationFOS: Physical sciences01 natural sciencesJET FRAGMENTATIONPartícules (Física nuclear)law.inventionHigh Energy Physics - Experimentsymbols.namesakeHigh Energy Physics - Experiment (hep-ex)NEUTRINO HELICITYLUND MONTE-CARLO; CHARGED WEAK-INTERACTIONS; RIGHT-SYMMETRICAL MODEL; MICHEL PARAMETERS; NEUTRINO HELICITY; RADIATIVE-CORRECTIONS; JET FRAGMENTATION; ENERGIES; LEPTON; PARTICLESlaw0103 physical sciences[PHYS.HEXP]Physics [physics]/High Energy Physics - Experiment [hep-ex]RADIATIVE-CORRECTIONSPARTICLESTensor010306 general physicsColliderLEPTONEngineering (miscellaneous)Charged currentDELPHIPhysics010308 nuclear & particles physicsMICHEL PARAMETERSCoupling (probability)HelicityLARGE ELECTRON POSITRON COLLIDERRIGHT-SYMMETRICAL MODELPARTICLE PHYSICS; LARGE ELECTRON POSITRON COLLIDER; DELPHIsymbolsMichel parametersPARTICLE PHYSICSFísica nuclearHigh Energy Physics::ExperimentAstrophysics::Earth and Planetary AstrophysicsParticle Physics - ExperimentLeptonEuropean physical journal : C : particles and fields
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Search for eta and eta ' -> pi(+)e(-)(v)over-bar(e) + c.c. decays in J/psi -> phi eta and phi eta '

2013

Using a sample of 225.3 million J/psi events collected with the BESIII detector at the BEPCII e(+)e(-) collider in 2009, searches for the decays of eta and eta' -> pi(+)e(-)(v) over bar (e) + c.c. in J/psi -> phi eta and phi eta' are performed. The phi signals, which are reconstructed in K+K- final states, are used to tag eta and eta' semileptonic decays. No signals are observed for either eta or eta', and upper limits at the 90% confidence level are determined to be 7.3 x 10(-4) and 5.0 x 10(-4) for the ratios B(eta ->pi(+)e(-)(v) over bar (e) + c.c)/B(eta ->pi(+)pi(-)pi(0)) and B(eta'->pi(+)e(-)(v) over bar (e) + c.c)/B(eta'->pi(+)pi(-)eta) respectively. These are the first upper- limit v…

Weak-InteractionsStandard ModelGev/CHigh Energy Physics::ExperimentMesonNuclear ExperimentDecays
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