Related papers: The Strange Quark Mass from QCD Sum Rules
We apply, to the new OPAL data on V+A strange spectral functions, a suitable combination of QCD spectral sum rules directly sensitive to the combination of strange quark (m_s) and tachyonic gluon (\lambda^2) masses . Using the mean value of…
Recent experimental improvements on K-decay data allow for a precise extraction of the strangeness-changing scalar K pi form factor and the related strange scalar spectral function. On the basis of this scalar as well as the corresponding…
We present a determination of the strange quark mass for two flavours (nf=2) of light dynamical quarks using the axial Ward identity. The calculations are performed on the lattice using O(a) improved Wilson fermions and include a fully…
The correlators of light-quark currents contain mass-singularities of the form log(m^2/Q^2). It has been known for quite some time that these mass- logarithms can be absorbed into the vacuum expectation values of other operators of…
The concept of QCD sum rules is extended to bound states composed of particles with finite mass such as scalar quarks or strange quarks. It turns out that mass corrections become important in this context. The number of relevant corrections…
The QCD up- and down-quark masses are determined from an optimized QCD Finite Energy Sum Rule (FESR) involving the correlator of axial-vector current divergences. In the QCD sector this correlator is known to five loop order in perturbative…
We discuss the ratio of hadronic to leptonic tau-decays, that can be expanded in an operator product expansion. The sensitivity to the strange mass is increased, if only the flavor-breaking difference of strange to non-strange currents is…
We study the properties of the light vector mesons ($\rho$, $\omega$ and $\phi$) in strange hadronic matter using the QCD sum rule approach. The in-medium masses of the vector mesons are calculated from the modifications of the light quark…
The standard procedure to determine (analytically) the values of the quark masses is to relate QCD two-point functions to experimental data in the framework of QCD sum rules. In the case of the light quark sector, the ideal Green function…
We determine the charm quark mass ${\hat m}_c({\hat m}_c)$ from QCD sum rules of moments of the vector current correlator calculated in perturbative QCD. Only experimental data for the charm resonances below the continuum threshold are…
We determine the masses of the light and the strange quarks in the $\bar{MS}$-scheme using our high-statistics lattice simulation of QCD with dynamical Wilson fermions. For the light quark mass we find $m^{light}_{\bar{MS}}(2 GeV) = 2.7(2)…
We include the new, five-loop, O(alpha_s^4) correction into the QCD sum rule used for the s-quark mass determination. The pseudoscalar Borel sum rule is taken as a study case. The OPE for the correlation function with N^4LO, O(alpha_s^4)…
We calculate the light meson spectrum and the light quark masses by lattice QCD simulation, treating all light quarks dynamically and employing the Iwasaki gluon action and the nonperturbatively O(a)-improved Wilson quark action. The…
The mass of the strange quark is determined from SU(3)-breaking effects in the tau hadronic width. Compared to previous analyses, the contributions from scalar and pseudoscalar spectral functions, which suffer from large perturbative…
We determine the charm quark mass $\hat{m}_c$ from QCD sum rules of moments of the vector current correlator calculated in perturbative QCD at ${\cal O} (\hat\alpha_s^3)$. Only experimental data for the charm resonances below the continuum…
Using the O(a) Symanzik improved action an estimate is given for the strange quark mass for unquenched (n_f=2) QCD. The determination is via the axial Ward identity (AWI) and includes a non-perturbative evaluation of the renormalisation…
We reconsider the determinations of the strange quark mass m_s from e+e- into hadrons data using a new combination of FESR and revisiting the existing tau-like sum rules by including non-resonant contributions to the spectral functions. To…
The light quark masses are determined using a new QCD Finite Energy Sum Rule (FESR) in the pseudoscalar channel. This FESR involves an integration kernel designed to reduce considerably the contribution of the (unmeasured) hadronic…
We determine the strange and light quark condensates in full lattice QCD for the first time. This is done by direct calculation of the expectation value of the trace of the quark propagator followed by subtraction of the appropriate…
The perturbative quark mass corrections to the tau hadronic width are studied to O(alpha_s^3 m_q^2). Including up to dimension four corrections, we get m_s(4 GeV^2)=(143 \pm 42) MeV [m_s(1 GeV^2)=(193 \pm 59) MeV ]. Possible improvements to…