Interaction of eta mesons with nuclei

Abstract

Back in the mid eighties, a new branch of investigation which was related to the interaction of eta mesons with nuclei came into existence. It started with the theoretical prediction of possible exotic states of eta mesons and nuclei bound by the strong interaction and later developed into an extensive experimental program to search for such unstable states as well as understand the underlying interaction via eta meson producing reactions. The vast literature of experimental as well as theoretical works which studied various aspects of eta producing reactions such as the ${\pi }^{+}$ $n$ $\to \eta p$, $pd{\to }^3$He $\eta$, $p{}^6$Li ${\to }^7$Be $\eta$ and ${\gamma }^3$He $\to \eta$ X, to name a few, had but one objective in mind: to understand the eta - nucleon ($\eta N$) and hence the $\eta$-nucleus interaction which could explain the production data and confirm the existence of some $\eta$-mesic nuclei. In spite of these efforts, there remain uncertainties in the knowledge of the $\eta N$ and hence the $\eta$-nucleus interaction. The present review is hence an attempt to bind together the findings in these works and draw some global and specific conclusions which can be useful for future explorations.

references added

References in corpus (18)

• Measurement of the dp -->3He eta reaction near threshold
• Coupled-channels study of the ${\pi }^{-}p\to \eta n$ process
• Photoproduction of eta meson within a coupled-channels K-matrix approach
• Meson-baryon scattering lengths in HB$\chi$PT
• Quantum reflection and dwell times of metastable states
• Level crossing of particle-hole and mesonic modes in eta mesic nuclei
• Formation of eta-mesic nuclei by (pi,N) reaction and N^*(1535) in medium
• Cross Section and Tensor Analysing Power of the $\vec{d}d\to \eta \alpha$ Reaction Near Threshold
• Precision study of the d+p->3He+eta reaction for excess energies between 20 and 60 MeV
• Mechanism of the close-to-threshold production of the eta meson
• Eta meson production in nucleon-nucleon collisions within an effective Lagrangian model
• Possible eta-mesic 3He states within the finite rank approximation
• Small eta-N scattering lengths favour eta-d and eta-alpha states
• Interference and nuclear medium effects on the eta-mesic nuclear spectrum
• A study of the $pd\to pd\eta$ reaction
• A large acceptance scintillator detector with wavelength shifting fibre read-out for search of eta-nucleus bound states
• Comment on "Hadronic ${}^3$He$\eta$ production near threshold"
• Near threshold eta meson production in dp collisions

Cited by in corpus (32)

• Meson-nucleus potentials and the search for meson-nucleus bound states
• Etaprime and Eta Mesons with Connection to Anomalous Glue
• Role of vector and pseudoscalar mesons in understanding $1/2^{-}$ $N^{\ast }$ and $\Delta$ resonances
• Search for eta-mesic 4He in the dd->3He n pi0 and dd->3He p pi- reactions with the WASA-at-COSY facility
• Search for Quasi Bound $\eta$ Mesons
• Eta-mesic nuclei: past, present, future
• Constraining the optical potential in the search for eta-mesic 4He
• Momentum distribution of N${}^{\ast }$ in nuclei
• Cross section ratio and angular distributions of the reaction p + d -> 3He + eta at 48.8 MeV and 59.8 MeV excess energy
• Upper limits for the production of the eta-mesic Helium in the dd ->3Henpi0 and dd -> 3Heppi- reactions
• Resonance-like structure near the $\eta d$ threshold in the $\gamma d${$\to$}${\pi }^0\eta d$ reaction
• Few-body aspects of the near threshold pseudoscalar meson production
• Total and differential cross sections of $\eta$-production in proton-deuteron fusion for excess energies between $Q_{\eta }=13\text{MeV}$ and $Q_{\eta }=81\text{MeV}$
• Search for the $\eta$ mesic ${}^3$He in the $pd\to dp{\pi }^0$ reaction with the WASA-at-COSY facility
• $\eta$ and ${\eta }^{\prime }$ mesons in nuclear matter and nuclei
• Search for eta mesic 3He with the WASA-at-COSY facility in the pd-> 3He 2gamma and pd-> 3He 6gamma reactions
• Status and Perspectives of the Search for Eta-Mesic Nuclei
• Different manifestations of S-matrix poles
• Study of the N N eta' production with COSY-11
• Search for the manifestation of the mesic-nuclei on the dd-->3HeNpi excitation function measured with WASA-at-COSY
• Luminosity determination for the proton-deuteron reaction using pd -> 3He eta channel with WASA-at-COSY detector
• Luminosity determination for the deutron-deutron reactions using free and quasi-free reactions with WASA-at-COSY detector
• Search for the eta-mesic Helium bound state with the WASA-at-COSY facility
• Theoretical study of the $\gamma d\to {\pi }^0\eta d$ reaction
• Status of the search for $\eta$-mesic nuclei with particular focus on $\eta$-Helium bound states
• Formation of eta'(958) Meson Bound States by the 6Li(gamma,d) reaction
• Exotic properties of N^*(1895) and its impact on photoproduction of light hyperons
• Search for the 4He-eta bound state in dd->(4He-eta)_{bound}->3He n pi0 and dd->(4He-eta)_{bound}->3He p pi- reactions with the WASA-at-COSY facility
• $\eta$ bound state: theory and experiment
• The $\eta$ decay into 3$\pi$ in asymmetric nuclear medium
• Production and interaction of the eta meson with nucleons and nuclei
• Close to threshold eta' meson production in proton-proton collisions at COSY-11