Related papers: $\eta$ bound states in nuclei
The large values of the singlet and triplet scattering lengths locate the two-nucleon system close to the unitary limit, the limit in which these two values diverge. As a consequence, the system shows a continuous scale invariance which…
We reanalyze data from ELSA on $\omega$ production in nuclei, from where claims of a large shift of the mass were made earlier, which are tied to a certain election of the background in nuclei, very different in shape to the one on the…
The properties (masses and decay widths) of the $\phi$ meson are investigated in nuclear matter from the $\phi$ meson self-energy, using the tree-level $\phi K\bar{K}$ Lagrangian, and, incorporating in-medium masses of (anti)kaons…
The excitation function and momentum distribution of $\eta^\prime$ mesons have been measured in photon induced reactions on $^{12}{}$C in the energy range of 1250-2600 MeV. The experiment was performed with tagged photon beams from the ELSA…
The mass and decay width of the $\phi$ meson in cold nuclear matter are computed in an effective Lagrangian approach, with the medium dependence of these properties obtained by evaluating kaon-antikaon loop contributions to the $\phi$…
The experimental data of the COSY-GEM Collaboration for the recoil-free transfer reaction p (27Al, 3He) \pi - p' X, leading to the formation of bound state of eta (\eta) meson in 25Mg nucleus, is reanalyzed in this paper. In particular,…
A microscopic treatment of $\eta$--nucleus scattering is presented. When applying the underlying exact integral equations, the excitation of the target are neglected, and an input $\eta N$ amplitude is chosen which reproduces the…
Experimental evidence for antikaon-nuclear quasibound states is briefly reviewed. Theoretical and phenomenological arguments for and against deep antikaon-nucleus potentials which might allow for narrow quasibound states are reviewed, with…
We theoretically investigate a possibility of an $\eta ^{\prime} d$ bound state and its formation in the $\gamma d \to \eta d$ reaction. First, in the fixed center approximation to the Faddeev equations we obtain an $\eta ^{\prime} d$ bound…
We discuss the in-medium mass of the eta-prime meson under partial restoration of chiral symmetry. The chiral SU(3)\otimes SU(3) symmetry tells us the flavor singlet pseudoscalar meson eta-prime should degenerate with the octet $\eta$ meson…
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…
The nuclear symmetry energy plays important role on the structure of finite nuclei as well as on the bulk properties of neutron stars. However, its values at high densities are completely uncertain and the corresponding experimental data…
There is much speculation and a modest amount of evidence that certain mesons might form quasi-bound states with nuclei to produce really exotic states of matter. For this to be a practical possibility, the interaction between the meson and…
I is argued here that (at least light) nuclei may reside in a sweet spot: bound weakly enough to be insensitive to the details of the interaction, but dense enough to be insensitive to the exact values of the large two-body scattering…
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…
The role played by subthreshold meson-baryon dynamics is demonstrated in kaonic-atom, Kbar-nuclear and eta-nuclear bound-state calculations within in-medium models of Kbar-N and eta-N interactions. New analyses of kaonic atom data reveal…
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…
Different electron states in atom are proposed. The states are bound to the electrostatic field of atomic nucleus cut off on its size. The states exist solely during acceleration of the atom exceeding the certain large value. The binding…
In this paper the search for eta-mesic nuclei with particular focus on light $\eta$-He bound states is reviewed. A brief description of recent theoretical studies and experimental results is presented.
Investigations of in-medium properties of the {\eta}'-meson are presented. The photoproduction of {\eta}'-mesons off C, Ca, Nb and Pb nuclei has been measured with the Crystal Barrel/TAPS detector system at the ELSA accelerator in Bonn.…