Related papers: In-medium chiral perturbation theory beyond the me…
A critical point of second order, belonging to the universality class of the 3d Ising model, has recently been advocated as a strong candidate for the critical behaviour (at high temperatures) of QCD with non-zero quark masses. The…
It is shown in a systematic way that the instanton dilute model can be combined with the global colour symmetry model to form a new nonperturbative QCD model. Based on the quark propagator derived in the instanton dilute liquid…
We present our preliminary results concerning the charged/neutral pion mass difference $M_{\pi^{+}} - M_{\pi^{0}}$ at order $\mathcal{O}(\alpha_{em})$ in the QED interactions, and for $M_{\pi^{+}} - M_{\pi^{0}}$ at order $\mathcal{O}\left(…
We present and discuss a systematic calculation, based on two-loop chiral perturbation theory, of the pion-nuclear s-wave optical potential. A proper treatment of the explicit energy dependence of the off-shell pion self-energy together…
It is well known that neutrinoless double decay is going to play a crucial role in settling the neutrino properties, which cannot be extracted from the neutrino oscillation data. It is, in particular, expected to settle the absolute scale…
We compute the light-cone momentum distributions of pions in the nucleon in chiral effective theory using both pseudovector and pseudoscalar pion-nucleon couplings. For the pseudovector coupling we identify \delta-function contributions…
The leading-particle effect and the factorization property of the scattering amplitude in the impact parameter space are used to study semiclassical production of pions in the central region. The mechanism is related to the isospin-uniform…
Using QCD sum rules and chiral SU(3) model, we investigate the effect of temperature, density, strangeness fraction and isospin asymmetric parameter on the shift in masses and decay constants of the pseudoscalar $D$ and $B$ meson in…
The nucleon-pion-state contributions to QCD 2- and 3-point functions used in the calculation of the nucleon axial charge are studied in chiral perturbation theory. For sufficiently small quark masses and large volumes the nucleon-pion…
The near-threshold n p -> d pi0 cross section is calculated in chiral perturbation theory to next-to-leading order in the expansion parameter sqrt{M m_pi}/Lambda_chi. At this order irreducible pion loops contribute to the relevant…
The role of the quark condensate for the low energy structure of QCD is discussed in some detail. In particular, the dependence of M_pi on m_u and m_d and the low energy theorems for the pi-pi scattering amplitude are reviewed. The new data…
Single pion production off nucleons is studied in the framework of relativistic baryon chiral perturbation theory at tree level with the inclusion of the terms from the dimension two effective pion-nucleon Lagrangian. The five appearing…
We calculate the energies of quarkonium bound states in the presence of a medium of nonzero isospin density using lattice QCD. The medium, created using a canonical (fixed isospin charge) approach, induces a reduction of the quarkonium…
By matching 1/m^2 divergences in finite-volume two-point correlation functions of the scalar or pseudoscalar densities with those obtained in chiral perturbation theory, we derive a relation between the Dirac operator zero-mode…
We calculate the pion-pion elastic scattering phase shifts for pion masses from the chiral limit to values of interest for lattice studies. At low energies, we use the standard Chiral Perturbation Theory expressions to one and two loops. In…
Traditional few-body descriptions of pion production use integral equations to sum the strong interactions nonperturbatively. Although much physics is thereby included, there has not been a practical way of incorporating the constraints of…
We continue the program [1] of carving out the space of large $N$ confining gauge theories by modern S-matrix bootstrap methods, with the ultimate goal of cornering large $N$ QCD. In this paper, we focus on the effective field theory of…
We utilize the eigenvalue filtering technique combined with the stochastic estimate of the mode number to determine the eigenvalue spectrum. Simulations of (2 + 1)-flavor QCD are performed using the Highly Improved Staggered Quarks…
The longest-range part of the nuclear force due to the one-pion exchange governs the energy dependence of the scattering amplitude in the near-threshold region and imposes correlations between the coefficients in the effective range…
Recent work in low energy pion physics is reviewed. One of the exciting new developments in this field is that simulations of QCD on a lattice now start providing information about the low energy structure of the continuum theory, for…