6533b7dcfe1ef96bd1272b07
RESEARCH PRODUCT
Strange quark condensate from QCD sum rules to five loops
Karl SchilcherCesareo A. DominguezN. F. Nasrallahsubject
PhysicsQuantum chromodynamicsQuarkNuclear and High Energy PhysicsStrange quarkQCD sum rulesParticle physicsHigh Energy Physics::LatticeHadronNuclear TheoryHigh Energy Physics::PhenomenologyFOS: Physical sciencesPseudoscalarHigh Energy Physics - PhenomenologyHigh Energy Physics - Phenomenology (hep-ph)Degree of a polynomialHigh Energy Physics::ExperimentNuclear ExperimentEnergy (signal processing)description
It is argued that it is valid to use QCD sum rules to determine the scalar and pseudoscalar two-point functions at zero momentum, which in turn determine the ratio of the strange to non-strange quark condensates $R_{su} = \frac{}{}$ with ($q=u,d$). This is done in the framework of a new set of QCD Finite Energy Sum Rules (FESR) that involve as integration kernel a second degree polynomial, tuned to reduce considerably the systematic uncertainties in the hadronic spectral functions. As a result, the parameters limiting the precision of this determination are $\Lambda_{QCD}$, and to a major extent the strange quark mass. From the positivity of $R_{su}$ there follows an upper bound on the latter: $\bar{m_{s}} (2 {GeV}) \leq 121 (105) {MeV}$, for $\Lambda_{QCD} = 330 (420) {MeV} .$
| year | journal | country | edition | language |
|---|---|---|---|---|
| 2007-11-26 |