Related papers: Medium effects to the N(1535) resonance and eta me…
Eta-mesic nucleus or the quasibound nuclear state of an eta ($\eta$) meson in a nucleus is caused by strong-interaction force alone. This new type of nuclear species, which extends the landscape of nuclear physics, has been extensively…
We are going to perform an inclusive spectroscopy experiment of eta' mesic nuclei with the 12C(p,d) reaction to study in-medium properties of the eta' meson. In nuclear medium, the eta' meson mass may be reduced due to partial restoration…
The missing-mass spectrum obtained in a recoil-free transfer reaction p($^{27}$Al,$^{3}$He)$\pi^{-}$p'X is analyzed. We find that the observed peak structure arises from the coherent contributions from two reaction processes in the energy…
In-medium modification of the eta' mass is discussed in the context of partial restoration of chiral symmetry in nuclear medium. We emphasize that the U_A(1) anomaly effects causes the eta'-eta mass difference necessarily through the chiral…
The $\eta$ meson can be bound to atomic nuclei. Experimental search is discussed in the form of final state interaction for the reactions $dp\to{^3\text{He}}\eta$ and $dd\to{^4\text{He}}\eta$. For the latter case tensor polarized deuterons…
The self-energy of an eta meson in the nuclear medium is calculated in a chiral unitary approach. A coupled channel Bethe-Salpeter equation is solved to obtain the effective eta-N interaction in the medium. The base model reproduces well…
We discuss theoretically the possibility of observing the bound states of the \eta and \eta'(958) mesons in nuclei. We apply the NJL model to study the \eta and \eta' meson properties at finite density and calculate the formation cross…
The strong energy dependence of the s-wave eta-N scattering amplitude at and below threshold, as evident in coupled-channels K-matrix fits and chiral models that incorporate the S11 N*(1535) resonance, is included self-consistently in…
The nuclear states of \bar K and \eta are bound by a similar mechanism - the excitations of nucleons to \Lambda (1405) and N*(1535) resonant states. The observed large differences in binding energies are understood in terms of separation of…
Recent results for the $\eta_c$- and $J/\psi$-nucleus bound state energies for various nuclei are presented. The attractive potentials for the $\eta_c$ and $J/\psi$ mesons in the nuclear medium originate, respectively, from the in-medium…
The \eta-meson collision with light nuclei, ^2H, ^3H, ^3He, and ^4He, is considered on the basis of a microscopic approach which utilises Faddeev type and Lippmann-Schwinger equations. The nuclear hamiltonian is approximated by the finite…
We present results for the $\eta_c$-nucleus bound state energies for various nuclei using an effective Lagrangians approach. The attractive potentials for the $\eta_c$ in the nuclear medium originate from the medium-modified intermediate $D…
A relativistic non-local model for the inclusive photoproduction of $\eta$ mesons from complex nuclei is introduced. The model is based on the dominance of the S$_{11}$(1535) resonance. We compare the results of our calculations with the…
Recent experiments studying the meson-nucleus interaction to extract meson-nucleus potentials are reviewed. The real part of the potentials quantifies whether the interaction is attractive or repulsive while the imaginary part describes the…
The isoscalar $\eta$ and $\eta'$ mesons are special in QCD, being linked both to chiral symmetry and to non-perturbative glue associated with the axial anomaly. The properties of these mesons in medium are sensitive to how these dynamics…
The coherent photoproduction of $\eta$-mesons on spin-zero nuclei is studied in a relativistic, non-local model, which we have previously applied to the coherent photoproduction of pions. We find that different off-shell extrapolations of…
Starting from a recent model of the eta'N interaction, we evaluate the eta'-nucleus optical potential, including the contribution of lowest order in density, t rho/2m_eta', together with the second order terms accounting for eta' absorption…
We report on the experimental search for the bound state of an $\eta$ meson and $^{3}\hspace{-0.03cm}\mbox{He}$ nucleus performed using the WASA-at-COSY detector setup. In order to search for the $\eta$-mesic nucleus decay, the…
The optical potential for the $\eta$-meson is calculated. This is based on a new determination of a large $\eta$-N scattering length and recent experiments of $\eta$ production in two nucleon collisions. These determine the $\eta$ - nuclear…
The eta' meson mass may be reduced due to partial restoration of chiral symmetry. If this is the case, an eta'-nucleus system may form a nuclear bound state. We plan to carry out a missing-mass spectroscopy with the 12C(p,d) reaction at…