相关论文: Bounds on the bound \eta ^3He system

The importance of three-body dynamics in the $\eta np$ system in elastic and inelastic $\eta$-deuteron scattering as well as coherent and incoherent $\eta$ photoproduction on the deuteron in the energy region from threshold up to 30 MeV…

The binding energies of the five bound rotational levels $J=0-4$ in the highest vibrational level $v=14$ in the X$^1\Sigma_g^+$ ground electronic state of H$_2$ were measured in a three-step ultraviolet-laser experiment. Two-photon…

Three-boson Efimov physics is well known in the bound-state regime, but far less in the three-particle continuum at negative two-particle scattering length where Efimov states evolve into resonances. They are studied solving rigorous…

We analyze the data on the total cross sections for the $dd \to \eta{}^4{\rm He}$ reaction close to threshold and look for possible $\eta ^4 {\rm He}$ bound states. We develop a framework in which the $\eta ^4{\rm He}$ optical potential is…

We start from a parity-breaking MCS QED$_{3}$ model with spontaneous breaking of the gauge symmetry as a framework for evaluation of the electron-electron interaction potential and for attainment of numerical values for the e-e bound state.…

The possibility for the existence of unstable bound states of the S11 nucleon resonance N$^*$(1535) and nuclei is investigated. These quasibound states are speculated to be closely related to the existence of the quasibound states of the…

Highly-elongated quasi-one-dimensional cold atom samples have been studied extensively over the past years experimentally and theoretically. This work determines the energy spectrum of two identical fermions and a third distinguishable…

The 4He3 system is investigated using a hard-core version of the Faddeev differential equations and realistic 4He-4He interactions. We calculate the binding energies of the 4He trimer but concentrate in particular on scattering observables.…

We conduct a search for the 4He-eta bound state with WASA-at-COSY facility, via a measurement of the excitation functions for the dd->3Heppi- reaction, where the outgoing p-pi- pairs originate from the conversion of the eta meson on a…

We present predictions for the the K^- \alpha scattering length obtained within the framework of the multiple scattering approach. Evaluating the pole position of the K^- \alpha scattering amplitude within the zero range approximation, we…

The differential and total cross sections for the d+p->3He+eta reaction have been measured in a high precision high statistics COSY-ANKE experiment near threshold using a continuous beam energy ramp up to an excess energy Q of 11.3 MeV with…

An exclusive measurement of the excitation function for the dd->3Heppi- reaction was performed at the Cooler Synchrotron COSY-Juelich with the WASA-at-COSY detection system. The data were taken during a slow acceleration of the beam from…

We argue that eta bound states in nuclei are sensitive to the singlet component in the eta. The bigger the singlet component, the more attraction and the greater the binding. Thus, measurements of eta bound states will yield new information…

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…

The search for 4He-eta bound states was performed with the WASA-at-COSY facility via the measurement of the excitation function for the dd->3He n pi0 and dd->3He p pi- processes. The beam momentum was varied continuously between 2.127 GeV/c…

Unstable states of the eta meson and the 3He nucleus predicted using the time delay method were found to be in agreement with a recent claim of eta-mesic 3He states made by the TAPS collaboration. Here, we extend this method to a…

For atoms with large scattering length, the dependence of the 3-body recombination rate on the collision energy is determined by the scattering length and the Efimov 3-body parameters and can be expressed in terms of universal functions of…

The search for a quasi bound $\eta$ meson in atomic nuclei is reviewed. This tentative state is studied theoretically as well as experimentally. The theory starts from elastic $\eta$ nucleon scattering which is derived from production data…

From the many-body T-matrix the condition for a medium-dependent bound state and its binding energy is derived for a homogeneous interacting Bose gas. This condition provides the critical line in the phase diagram in terms of the…

The usefulness of the three-body mechanism of $\eta$-meson production is tested by extending to high energies a recently developed two step model of the $p d \to ^3$He $\eta$ reaction by us, which was successful in reproducing the energy…