Speaker
Description
The interactions between $\eta$-meson and nucleons are studied by the unification of chiral SU(3) model and chiral perturbation theory. The $\eta$ and nucleon interactions for the next to leading order terms are derived by expanding the $\eta N$ interaction Lagrangian term within the chiral perturbation theory. Using the chiral SU(3) model, we calculate the in-medium scalar density, $\rho_s$ for different values of temperature, $T$, isospin asymmetry, $I$, and nucleonic density, $\rho_N$. Further, by clubbing the $\eta N$ equation of motion with the scalar density, the in-medium mass and optical potential of $\eta$ meson is derived. The asymmetric matter affects are introduced through the scalar-isovector field $\delta$ and the vector-isovector field $\rho$. We find attractive mass-shift of the $\eta$ meson which becomes more attractive with the increase in density. The negative mass-shift indicates the possibility of the formation of $\eta$-mesic nuclei.
