We have shown that self interaction effects in massive quantum electrodynamics can lead to the formation of bound states of quark antiquark pairs. A current-current fermion coupling term is introduced, which induces a well in the potential energy profile. Explicit expressions of the effective potential and renormalized parameters are provided. Email address: ¡[email protected]¿

In this paper, we discuss a possibility to improve constraints on spin-dependent short-range interactions in the range of 1 – 200μm significantly. For such interactions, our constraints are without competition at the moment. They were obtained through the observation of gravitationally bound states of ultracold neutrons. We are going to improve these constraints by about three orders of magnitu...

The 1sns S Rydberg series in a two-electron system with the charge of the nucleus, Z'1, is treated by means of the quantum-defect theory. Comparison with configuration interaction calculations suggests that the quantum-defect expression for the energy levels becomes asymptotically exact as Z→1. This provides an analytic description of the disappearance of the 1sns S bound states when Z approach...

The one-dimensional problem of N particles with contact interaction in the presence of a tunable transmitting and reflecting impurity is investigated along the lines of the coordinate Bethe ansatz. As a result, the system is shown to be exactly solvable by determining the eigenfunctions and the energy spectrum. The latter is given by the solutions of the Bethe ansatz equations which we establis...

An impurity bond J ′ in a periodic 1D antiferromagnetic, spin 1 chain with exchange J is considered. Using the numerical density matrix renormalization group method, we find an impurity energy level in the Haldane gap, corresponding to a bound state near the impurity bond. When J ′ < J the level changes gradually from the edge of the Haldane gap to the ground state energy as the deviation dev =...

The correct use of energy-dependent single-particle level (s.p.l.) densities within particle-hole state densities based on the equidistant spacing model (ESM) is analysed. First, an analytical expression is obtained following the convolution of energy-dependent excited-particle and hole densities. Next, a comparison is made with results of the ESM formula using average s.p.l. densities for the ...

The deuteron is described as a quantum state on a ten-dimensional manifold M 10 of Skyrme fields of degree two, which are obtained by calculating the holonomy of SU (2) instantons. The manifold M 10 includes both toroidal configurations of minimal energy and configurations which are approximately the product of two Skyrmions in the most attractive relative orientation. The quantum Hamiltonian i...

The collision of an antiproton and a hydrogen atom at ultralow energies is described in hyperspherical coordinates. An adiabatic approximation leads to potential-energy curves that can be used to describe the dynamics of capture in the p̄ -H(1s) collision. A unified formulation of the collision and capture processes leading to formation of pp̄ bound states emerges. Both Pn(nl)-e ‘‘atomic-type’’ a...

In the energy sudden (ES) approximation for nonreactive molecular collisions,there exist factorization relations by which an arbitrary T‐matrix element can be predicted as a spectroscopic linear combination of those out of some other, input state. These were first discovered for ground state input but this restriction was later removed. This general form of the spectroscopicfactorization relati...

We investigate the bound states of heavy mesons with finite masses to a classical soliton solution in the Skyrme model. For a given model Lagrangian we solve the equations of motion exactly so that the heavy vector mesons are treated on the same footing as the heavy pseudoscalar mesons. All the energy levels of higher grand spin states as well as the ground state are given over a wide range of ...