相关论文: In medium effects on the $\phi$ meson

In this talk I summarize recently proposed mechanisms to understand pi pi scattering to 1 GeV in an effective chiral Lagrangian. The Lagrangian includes higher resonances in addition to pions consistently with the chiral symmetry. Iso-spin…

The $d^* \to d \pi \pi$ partial decay width has been calculated in a wave-function model for $d^*$ and $d$. It is found to be smaller than a previous estimate by a factor of 7. A previously proposed dependence on dibaryon sizes is…

An effective meson Lagrangian including a scalar glueball is constructed on the base of $U(3)\times U(3)$ chiral symmetry. The glueball is introduced into the meson Lagrangian by using the principle of scale invariance of an effective…

Within the framework of dispersion theory, we study the the processes $e^+e^-\to \phi(2170) \to \phi \pi\pi(K\bar{K})$. The strong pion-pion final-state interactions, especially the $K\bar{K}$ coupled channel in the $S$-wave, are taken into…

We study the properties of heavy mesons using a unitarized approach in a hot pionic medium, based on an effective hadronic theory. The interaction between the heavy mesons and pseudoscalar Goldstone bosons is described by a chiral…

We calculate the long distance contribution to $D^{+,0}\to\pi^{+,0}l^+l^-$ decays by the use of a vector meson dominance model, in which the $\phi$-meson plays the central role. The branching ratios obtained are $10^{-6}$ and a few times…

The composite operator formalism is applied to QCD at finite temperature to calculate the masses of scalar and pseudoscalar mesons. In particular the ratio of the sigma mass to the pion mass is an interesting measure of the degree of chiral…

In this work we compute the axion mass and, from this (exploiting a well-known relation), we also derive an expression for the QCD topological susceptibility in the finite-temperature case, both below and above the chiral phase transition…

We report on recent results on the decay of the phi into pi^+ pi^- and phi radiative decays into pi^0 pi^0 gamma and pi^0 eta gamma, which require the consideration of the final state interaction of a pair of mesons in a region inaccessible…

The decay widths \phi \to \gamma f_0(980) and \phi \to \gamma a_0(980) are calculated taking into account the finite widths of the scalar resonances f_0(980) and a_0(980). The latter are shown to be essential in order to obtain meaningful…

We study the neutral pion mass in the presence of an external arbitrary magnetic field in the framework of the linear sigma model coupled to quark (LSMq) at finite temperature. In doing so, we have calculated the pion self-energy,…

Starting from the Chiral Perturbation Theory Lagrangian, but keeping different masses for the charged and neutral mesons, and using a previously developed non-perturbative unitary scheme that generates the lightest meson-meson resonances,…

We investigate the $\bar{p} p \to \phi \phi$ reaction within an effective Lagrangian approach.We show that the inclusion of either a scalar meson $f_0$ or a tensor meson $f_2$ in the $s$-channel can lead to a fairly good description of the…

We study the influence of the finite damping width of pions on the in-medium properties of the rho-meson in an interacting meson gas model at finite temperature. Using vector dominance also implications on the resulting dilepton spectra…

The radiative decays of the phi meson are known to be a good source of information about the a0(980) and f0(980) scalar mesons. We discuss these decays starting from a non-linear model Lagrangian which maintains the (broken) chiral symmetry…

We study the effect of scalar-isoscalar $f_{0}(980)$ meson in the mechanism of the radiative $\phi\to \pi^{+}\pi^{-}\gamma$ decay. A phenomenological approach is used to study this decay by considering the contributions of $\sigma$-meson,…

We calculate the width for the omega -> pi pi decay in nuclear matter in a hadronic model including mesons, nucleons and Delta isobars. We find a substantial width of the longitudinally polarized omega modes, reaching ~100MeV for mesons…

We derive the chiral effective Lagrangian for heavy-light mesons in the heavy quark limit from QCD under proper approximations. The low energy constants in the effective Lagrangian are expressed in terms of the light quark self-energy. With…

Quarkonium properties at finite temperature have been studied with quark masses of the charm and bottom quarks. Our simulations have been performed in quenched QCD with the $O(a)$-improved Wilson quarks on large and fine isotropic lattices…

We study the behavior of the $\pi^0$ width as a function of temperature and density. We provide simple expressions for the neutral pion width in a hot and dense medium based on a renormalized version of the microscopic Nambu Jona Lasinio…