Related papers: Nuclear medium effects on the sigma mass and width
In order to assess the relevance of chiral dynamics in the scalar sector we address two recent problems: radiative decay of the $\phi$, for which there are quite recent data from Frascati, and the modification of the $\sigma$ properties in…
The properties of the $\bar K^*$ meson in dense matter are studied using a unitary approach in coupled channels within the framework of the local hidden gauge formalism. We obtain the $\bar K^*$ spectral function in the nuclear medium and…
We calculate the mass and width of the sigma meson in nuclear medium by considering that it couples to two virtual pions and to a pair of nucleon-antinucleon states and to particle-hole states. The mass is calculated by using the spectral…
We study the modification of the nucleon nucleon interaction in a nuclear medium in the scalar isoscalar channel, mediated by the exchange of two correlated ($\sigma$ channel) or uncorrelated pions. For this purpose we use a standard…
We study the in-medium properties of mesons $(\pi,\eta,\rho)$ and baryon resonances in cold nuclear matter within a coupled-channel analysis. The meson self energies are generated by particle-hole excitations. Thus multi-peak spectra are…
We use a nonperturbative approach which combines coupled channel Lippmann Schwinger equations with meson-meson potentials provided by the lowest order chiral Lagrangians. By means of one parameter, a cut off in the momentum of the loop…
The linear sigma model at finite baryonic density with a massive vector field is investigated considering that all the bosonic fields develop non zero expected classical values, eventually associated to condensates and corresponding to…
We have studied the decay of the \phi meson in nuclear matter by taking into account the renormalization of the K and \bar{K} mesons in the medium. We separate the contribution of the total width into different reaction channels, K\bar{K}…
We adopt a novel formalism for the low-energy analysis of the $\gamma p \to K^{+}\pi\Sigma$ photoproduction reaction to calculate the $\pi\Sigma$ invariant mass distributions in the $\Lambda(1405)$ resonance region. The approach adheres to…
Spectral functions of the pseudoscalar $D$ meson in the nuclear medium are analyzed using QCD sum rules and the maximum entropy method. This approach enables us to extract the spectral functions without any phenomenological assumption, and…
We investigate the role of the softening of the scalar-isoscalar (sigma) meson in the $\eta\rightarrow\pi^+\pi^-\pi^0$ and $3\pi^0$ decay widths in the symmetric nuclear medium using a linear sigma model. Our calculation shows that these…
The properties of strange mesons ($K$, $\bar K$ and $\bar K^*$) in dense matter are studied using a unitary approach in coupled channels for meson-baryon scattering. The kaon-nucleon interaction incorporates $s$- and $p$-wave contributions…
The mass spectra of nucleon resonances with spin 1/2, 3/2, and 5/2 are systematically studied in the constituent quark model with meson-quark coupling, which is inspired by the spontaneous breaking of chiral symmetry of QCD. The meson-quark…
The propagation of the scalar (\sigma and \delta) and vector (\omega and \rho) mesons in an iso-asymmetric nuclear matter is studied in detail, using the Walecka model. We calculate the invariant masses and spectral functions of the mesons,…
We present a model of baryonic matter which contains free constituent quarks in addition to bound constituent quarks in nucleons. In addition to the common linear sigma-model we include the exchange of vector-mesons. The percentage of free…
We first discuss the theoretical and phenomenological significance of the sigma meson ($\sigma$) in QCD. It is indicated that if the collective modes with the mass 500-600 MeV exists in the $I=J=0$ channel, various empirical facts in hadron…
In this study, we investigate the mass spectrum of $\pi$ and $\sigma$ mesons at finite chemical potential using the self-consistent NJL model and the Fierz-transformed interaction Lagrangian. The model introduces an arbitrary parameter…
We calculate the effect of many-body interactions in nuclear matter on the spectral function of $\rho$ and $\omega$ meson. In particular, we focus on the role played by baryon resonances in this context.
After giving brief discussions on the chiral condensate in hot and/or dense hadronic matter and the significance of the $\sigma$ meson in QCD, we discuss the importance of experiments using nuclear targets including ones with…
Properties of scalar--isoscalar mesons in a mass range from pi-pi threshold up to 1800 MeV are analysed using an unitary model with separable interactions in three decay channels: pi-pi, K-anti K and an effective 2pi-2pi. Different…