Search results for "Minimal subtraction scheme"

showing 2 items of 2 documents

Branching Ratios and Spectral Functions of $\tau$ Decays: final ALEPH measurements and physics implications

2005

The full LEP-1 data set collected with the ALEPH detector at the $Z$ pole during 1991-1995 is analysed in order to measure the $\tau$ decay branching fractions. Extensive systematic studies are performed, in order to match the large statistics of the data sample corresponding to over 300 000 measured and identified $\tau$ decays. Branching fractions are obtained for the two leptonic channels and eleven hadronic channels defined by their respective numbers of charged particles and $\pi^0$'s. Using previously published ALEPH results on final states with charged and neutral kaons, corrections are applied to the hadronic channels to derive branching ratios for exclusive final states without kao…

tau; branching fractions; Z poleParticle physicsbranching fractionElectron–positron annihilationHadronFOS: Physical sciencesGeneral Physics and AstronomyStrangeness01 natural sciencesAsymptotic freedomhadronicHigh Energy Physics - ExperimentNuclear physicsHigh Energy Physics - Experiment (hep-ex)tau decay; PION FORM-FACTOR; ELECTROWEAK RADIATIVE-CORRECTIONSquantum chromodynamictau decay0103 physical sciences[PHYS.HEXP]Physics [physics]/High Energy Physics - Experiment [hep-ex]tau010306 general physicsMinimal subtraction schemeQuantum chromodynamicsPhysics010308 nuclear & particles physicsZ poleHigh Energy Physics::PhenomenologyCharged particle3. Good healthsum rulebranching fractionsIsospinHigh Energy Physics::ExperimentELECTROWEAK RADIATIVE-CORRECTIONSParticle Physics - ExperimentPION FORM-FACTOR
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Light Quark Masses from Lattice Quark Propagators at Large Momenta

1999

We compute non-perturbatively the average up-down and strange quark masses from the large momentum (short-distance) behaviour of the quark propagator in the Landau gauge. This method, which has never been applied so far, does not require the explicit calculation of the quark mass renormalization constant. Calculations were performed in the quenched approximation, by using O(a)-improved Wilson fermions. The main results of this study are ml^RI(2GeV)=5.8(6)MeV and ms^RI(2GeV)=136(11)MeV. Using the relations between different schemes, obtained from the available four-loop anomalous dimensions, we also find ml^RGI=7.6(8)MeV and ms^RGI=177(14)MeV, and the MSbar-masses, ml^MS(2GeV)=4.8(5)MeV and …

PhysicsQuarkNuclear and High Energy PhysicsStrange quarkParticle physicsHigh Energy Physics::LatticeHigh Energy Physics::PhenomenologyNuclear TheoryHigh Energy Physics - Lattice (hep-lat)CHIRAL SYMMETRYFOS: Physical sciencesQuenched approximationNONPERTURBATIVE RENORMALIZATION CONSTANTSFermionDYNAMICAL WILSON FERMIONSPartícules (Física nuclear)RenormalizationHigh Energy Physics - PhenomenologyHigh Energy Physics - LatticeHigh Energy Physics - Phenomenology (hep-ph)Lattice gauge theoryHigh Energy Physics::ExperimentOperator product expansionMinimal subtraction schemeNuclear Experiment
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