We calculate the mass of vector meson in chiral symmetry restored vacuum. This is accomplished by separating four quark operators appearing and axial sum rules into symmetric breaking parts depending on contribution fermion zero modes. then identify each part from fit to masses. By taking be while keeping operator vacuum value, we find that between 550 600 MeV. demonstrates breaking, responsibl...

We improve the calculations of the η → π 0 γγ decay within the context of me-son chiral lagrangians. We use a chiral unitary approach for the meson-meson interaction, thus generating the a 0 (980) resonance and fixing the longstanding sign ambiguity on its contribution. This also allows us to calculate the loops with one vector meson exchange, thus removing a former source of uncertainty. In ad...

We improve the calculations of the h→p0gg decay within the context of meson chiral Lagrangians. We use a chiral unitary approach for the meson-meson interaction, thus generating the a0(980) resonance and fixing the long standing sign ambiguity on its contribution. This also allows us to calculate the loops with one vector meson exchange, thus removing a former source of uncertainty. In addition...

First results from lattice QCD revealing the chiral nonanalytic behavior of nucleon and ∆ baryon magnetic moments are presented. Numerical simulations in the light quark mass regime employing the nonperturbatively O(a)-improved conserved vector current are enabled via FLIC fermions. Quenched chiral perturbation theory for the nucleon and ∆ magnetic moments is derived to next to next to leading ...

We study the pion velocity near the critical temperature Tc of chiral symmetry restoration in QCD. Using chiral perturbation theory based on hidden local symmetry (HLS) as an effective field theory, where the chiral symmetry restoration is realized as the vector manifestation (VM), we show that the pion velocity for T → Tc is close to the speed of light, vπ(T ) = 0.83 − 0.99 which is at varianc...

We compute the chiral corrections to octet baryon axial vector currents through O(p3) in heavy baryon chiral perturbation theory, including both octet and decuplet baryon intermediate states. We include the latter in a consistent way by using the small scale expansion. We find that, in contrast to the situation at O(p2), there exist no cancellations between octet and decuplet contributions at O...