相关论文: Determining chiral couplings at NLO
We describe Scalar-Pseudoscalar partner degeneration at the QCD chiral transition in terms of the dominant low-energy physical states for the light quark sector. First, we obtain within model-independent one-loop Chiral Perturbation Theory…
We examine the shift in the chiral condensate due to a constant electromagnetic field at ${\cal O}(p^6)$ using SU(2) chiral perturbation theory and a realistic $M_\pi = 140 \textrm{MeV}$. We find that this value differs significantly from…
Reordering of the chiral perturbation series, proposed recently by Becher and Leutwyler in the framework of SU(2) baryonic ChPT, is applied to the SU(3) case. This results in improved convergence of the chiral expansion of static properties…
We determine the full structure of the leading (double-pole) divergences of O(p^6) in the meson sector of chiral perturbation theory. The field theoretic basis for this calculation is described. We then use an extension of this result to…
The main goal of this paper is to elaborate the model-framework parametrization of effective coupling constants of the extended chiral lagrangian which is suitable for the description of the low-energy matrix elements of vector,…
Within the framework of two-flavor covariant baryon chiral perturbation theory we have expressed the Chernyak-Zhitnitsky, Ioffe and Dosch currents in terms of chiral fields to provide leading one-loop extrapolation formulae for the leading…
An approximation is used that permits one to explicitly solve the two-point Schwinger-Dyson equations of the U(N) lattice chiral models. The approximate solution correctly predicts a phase transition for dimensions $d$ greater than two. For…
A detailed investigation of the low-energy chiral expansion is presented within a model truncation of QCD. The truncation allows for a phenomenological description of the quark-quark interaction in a framework which maintains the global…
We derive the sub-subleading two-pion exchange contributions to the three-nucleon force which appear at next-to-next-to-next-to-next-to-leading order in chiral effective field theory. In order to determine the low-energy constants, a…
We derive the scalar resonance coupling constants of resonance chiral theory from the Extended Nambu Jona-Lasinio model by using heat-kernel expansion.
We present preliminary results from our calculation of the low energy constants (LECs) of the chiral effective theory for 3, 4 and 5 color QCD with $N_f=2$ dynamical fermion flavors. We simulate with clover fermions over a range of lattice…
Quenched chiral perturbation is used to study the decay constants for heavy-light mesons beyond the leading order in 1/M. The results are used to estimate the error in quenched lattice calculations of the decay constants. For the double…
Chiral perturbation theory in the two-flavour sector allows one to analyse Green functions in QCD in a limit where the strange quark mass is considered to be large in comparison to the external momenta and to the light quark masses. In this…
Based on a dispersive approach, we apply the inverse amplitude method to unitarize one-loop SU(2) and SU(3) Chiral Perturbation Theory. Numerically, we find that this unitarization technique yields the correct complex analytic structure in…
Experimental data from hadronic $\tau$ decays allow for a precision determination of the slope of the $I=1$ vacuum polarization at zero momentum. We use this information to provide a value for the next-to-next-to-leading order (NNLO)…
We calculate the correlator between two external vector-currents having the quantum-numbers of a charged kaon. We give the renormalized expression to two loops in standard chiral perturbation theory in the isospin limit, which, as a…
We analize the most general low-energy effective lagrangian including local parity violating terms parametrized by an axial chemical potential $\mu_5$. This result is obtained following the external source method, up to $\mathcal{O}(p^4)$…
A methodology is given to test the QCD $N_f$=2 chiral transition, presently conjectured to be second order. Scaling forms for the correlation length, susceptibilities and equation of state are given which account for finite lattice spacing.…
We analyze the recently proposed Spectral Quark Model in the light of Chiral Perturbation Theory in curved space-time. In particular, we calculate the chiral coefficients $L_1, ..., L_{10}$, as well as the coefficients $L_{11}$, $L_{12}$,…
Using chiral perturbation theory and the large-$N_c$ expansion, we obtain expressions for the $\eta'$ mass and $\eta - \eta'$ mixing in terms of low-energy chiral Lagrangian parameters. This is accomplished through an intermediate step of…