Related papers: Scattering and resonances in the ^4He three-atomic…
Recent theoretical developments in the four-boson system with resonant interactions are described. Momentum-space scattering equations for the four-particle transition operators are used. The properties of unstable tetramers with…
Atom loss resonances in ultracold trapped atoms have been observed at scattering lengths near atom-dimer resonances, at which Efimov trimers cross the atom-dimer threshold, and near two-dimer resonances, at which universal tetramers cross…
A problem of collisions of atoms with two-channel zero-range interaction in an atomic waveguide is solved by using of a renormalization procedure. A matching of the solution to a solution of the related one-dimensional problem leads to…
We describe three-body collisions close to a Feshbach resonance by taking into account two-body scattering processes involving both the open and the closed channel. We extract the atom-dimer scattering length and the three-body…
Algorithm, based on explicit representations for analytic continuation of the T-matrix Faddeev components on unphysical sheets, is worked out for calculations of resonances in the three-body quantum problem. According to the…
The four-boson universality suggests the existence of the second excited tetramer state in a system of cold ${}^4\mathrm{He}$ atoms. It is not bound but could be seen as a resonance in the atom-trimer scattering. This process is rigorously…
The coupled-channel model [Phys. Rev. A {\bf 59}, 363 (1999)] that yields converged low-energy phase shifts, and exact binding and resonance features in Ps-H [Phys. Rev. A {\bf 59}, 2058 (1999)] is applied to study Ps-He$^+$ scattering.…
Algorithm, based on explicit representations for analytic continuation of the T-matrix Faddeev components on unphysical sheets, is worked out for calculations of resonances in the three-body quantum problem. According to the…
Scattering resonances play a central role in collision processes in physics and chemistry. They help building an intuitive understanding of the collision dynamics due to the spatial localization of the scattering wavefunctions. For…
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…
Elastic electron-helium-3 scattering is studied in the relativistic impulse approximation. The amplitudes for the three-nucleon system are obtained by solving the relativistic generalization of the Faddeev equations with a separable…
The Faddeev-Yakubowski equations have been solved in configuration space for the four nucleons system. Results for bound and scattering states in the isospin and S-wave approximation for different (T,S) channels are presented. The n-t…
A scattering resonance is one of the most striking quantum effects in low-temperature molecular collisions. Predicted decades ago theoretically, they have only been resolved experimentally for systems involving at most four atoms. Extension…
Relativistic Faddeev equations for three-body scattering at arbitrary energies are formulated in momentum space and in first order in the two-body transition-operator directly solved in terms of momentum vectors without employing a partial…
We use exact four-boson scattering equations in the momentum-space framework to study the universal properties of shallow Efimov tetramers and their dependence on the two-boson scattering length. We demonstrate that, in contrast to previous…
We study the collisional properties of an ultracold mixture of cesium atoms and dimers close to a Feshbach resonance near 550G in the regime of positive $s$-wave scattering lengths. We observe an atom-dimer loss resonance that is related to…
We report on a consistent, microscopic calculation of the bound and scattering states in the 4He system employing modern realistic two-nucleon and three-nucleon potentials in the framework of the resonating group model (RGM). We present for…
An Efimov trimer near the atom-dimer threshold can increase the atom loss rate in ultracold trapped atoms through the {\it avalanche mechanism} proposed by Zaccanti et al. A 3-body recombination event creates an energetic atom and dimer,…
We review the results obtained in the last four decades which demonstrate the Efimov nature of the $^4$He three-atomic system.
Faddeev-Yakubovski equations in configuration space are used to solve four nucleon problem for bound and scattering states. Different realistic interaction models are tested, elucidating open problems in nuclear interaction description. On…