Related papers: m_u + m_d from QCD-Hadron Duality
In this paper, we reanalyze the $I=0$ scalar channel with the improved Monte-Carlo based QCD sum rules, which combines the rigorous H\"older-inequality-determined sum rule window and a two Breit-Wigner type resonances parametrization for…
We revisit the isovector pseudoscalar sum rule determination of m_u+m_d, using families of finite energy sum rules known to be very accurately satisfied in the isovector vector channel. The sum rule constraints are sufficiently strong to…
QCD sum rules involving mixed inverse moment integration kernels are used in order to determine the running charm-quark mass in the $\bar{MS}$ scheme. Both the high and the low energy expansion of the vector current correlator are involved…
Results for the excited meson and baryon spectrum with two flavors of Chirally Improved sea quarks are presented. We simulate several ensembles with pion masses ranging from 250 to 600 MeV and extrapolate to the physical pion mass. Strange…
The mixing between q-qbar meson and qqbar-qqbar tetra-quark states is examined within an effective QCD Coulomb gauge Hamiltonian model. Mixing matrix elements of the Hamiltonian are computed and then diagonalized yielding an improved…
The shift of the p-wave $D_s$ meson mass due to coupling to the DK channel is calculated without fitting parameters using the chiral Lagrangian. As a result the original $Q\bar q$ mass 2.490 MeV generically calculated in the relativistic…
We have simulated QCD using 2+1 flavors of domain wall quarks on a $(2.74 {\rm fm})^3$ volume with an inverse lattice scale of $a^{-1} = 1.729(28)$ GeV. The up and down (light) quarks are degenerate in our calculations and we have used four…
We report on our on-going effort to calculate the properties of light nuclei directly from quarks and gluons based on lattice QCD. After briefly introducing our motivations and aims, we describe our strategy of fixing the strange quark mass…
The strange quark mass is determined from a QCD Finite Energy Sum Rule (FESR) optimized to reduce considerably the systematic uncertainties arising from the hadronic resonance sector, as well as from the poor convergence of the pseudoscalar…
We report on our preliminary results from the lattice-QCD computation of the hadronic light-by-light (HLbL) contribution to the anomalous magnetic moment of the muon. We use twisted-mass $N_f = 2 + 1 + 1$ gauge ensembles at the physical…
We perform a lattice study of heavy baryons, containing one ($\Lambda_b$) or two $b$-quarks ($\Xi_b$). Using the quenched approximation we obtain for the mass of $\Lambda_b$ $$ M_{\Lambda_b}= 5.728 \pm 0.144 \pm 0.018 {\rm GeV}.$$ The mass…
In this article, we study the $\Lambda_c$ and $\Lambda_b$ baryons in the nuclear matter using the QCD sum rules, and obtain the in-medium masses $M_{\Lambda_c}^*=2.335\,\rm{GeV}$, $M_{\Lambda_b}^*=5.678\,\rm{GeV}$, the in-medium vector…
We select sum rules from which one can extract directly reliable limits on the size of the chiral symmetry breaking light quark condensate $<\bar\psi\psi>$. Combined results from the nucleon and $B^*-B$ mass-splitting sum rules give a…
We report on our study of light hadron spectrum and quark masses in QCD with two flavors of dynamical quarks. Simulations are made with the plaquette gauge action and the non-perturbatively $O(a)$ improved Wilson quark action. We simulate 5…
A recent study shows that incorporating a new term into the thermodynamic potential density, as required by the thermodynamic consistency criterion, can effectively resolve the thermodynamic inconsistency problems of the conventional…
$QCD$ renormalization for the top-quark mass is calculated in a mass geometrical mean hierarchy, $m_d m_b = m_s^2$ and $m_u m_t = m_c^2$. The physical mass, $m_t(m_t) = 160 {\pm} 50 GeV$ is obtained, which agrees very well with electroweak…
We present a combination of measurements of the mass of the top quark, $m_{\rm top}$, performed by the CDF and D0 experiments at the Tevatron collider and the ATLAS and CMS experiments at the Large Hadron Collider (LHC). The Tevatron data…
An effective Coulomb gauge Hamiltonian, H_eff, is used to calculate the light (u-ubar-g), strange (s-sbar-g) and charmed (c-cbar-g) hybrid meson spectra. For the same two parameter H_eff providing glueball masses consistent with lattice…
Mass spectra of baryons consisting of two heavy (b or c) and one light quarks are calculated in the framework of the relativistic quark model. The light quark-heavy diquark structure of the baryon is assumed. Under this assumption the…
We report results for the interaction measure, pressure and energy density for nonzero temperature QCD with 2+1 flavors of improved staggered quarks. In our simulations we use a Symanzik improved gauge action and the Asqtad $O(a^2)$…