We investigate the influence of the real part of the in-medium pion optical potential on the pion dynamics in intermediate energy heavy ion reactions at 1 GeV/A. For different models, i.e. a phenomenological model and the ∆–hole model, a pionic potential is extracted from the dispersion relation and used in Quantum Molecular Dynamics calculations. In addition with the inelastic scattering proce...

The dependence of KS,L → ππγ decay probabilities on photon polarization is calculated. The phases of terms of amplitude that arise from the pion-pion interaction are obtained by using a simple realistic model of pion-pion interaction via virtual ρ-meson, instead of the ChPT. The results are compared with those of other authors and the origin of the discrepancies is explained. It is shown that t...

Pisa, Pisa, Italy. IHuang, Yang, and Lee, Phys. Rev. 108, 1348 (1957). H. Primakoff (unpublished) . H. Uberall, Nuovo cimento 6, 533 (1957). L. Wolfenstein, Nuovo cimento 1, 706 (1958). SCoffin, Sachs, and Tycko, Bull. Am. Phys. Soc. 3, 52 (1958). ILundy, Sens, Swanson, Telegdi, and Yovanovich, Phys. Rev. Letters 1, 102 (1958). J. C. Sens, Phys. Rev. 113, 79 (1959}. W. E. Chang, Revs. Modern Ph...

The Global Color-symmetry Model of QCD is extended to deal with a background electromagnetic field and the associated conserved current is identified for composite ¯ qq pion modes of the model. Although the analysis is limited to tree level in the bilocal fields that bosonize the model, the identified photon-pion vertex produces the charge form factor associated with ladder Bethe-Salpeter pion ...

Three-pion interferometry is investigated for new information on the spacetime structure of the pion source created in ultra-relativistic heavy-ion collisions. The twoand three-pion correlations are numerically computed for incoherent source functions based on the Bjorken hydrodynamical model, over a wide range of the kinematic variables. New information provided by threepion interferometry, di...

We investigate the exclusive two-pion production at the Z-pole through the process ee → Z → ππγ. In the kinematical region where the invariant mass of the two pions is much smaller than the mass of the Z boson, the process can be factorized into the convolution of a hard coefficient and a soft matrix element, the generalized distribution amplitude of two pions. We calculate the differential cro...

We have developed a field theory formalism to calculate in-medium properties of hadrons within a unified approach that exploits a single Lagrangian to describe simultaneously both matter background and meson fluctuations. In this paper we discuss the consequences on physical observables of a possible phase transition of hadronic matter taking place in the chiral limit. We pay special attention ...