During the last fifty years, nonneutral plasma physics has developed into a definite subfield
of basic research, whose main focus has been on the collective properties of systems …

This work is a collection of initial calculations and formal considerations within the Salpeter–
Sucher exact equal-time relativistic quantum electrodynamics framework. The calculations …

This work is concerned with two-spin-1/2-fermion relativistic quantum mechanics, and it is
about the construction of one-particle projectors using an inherently two-particle,“explicitly …

The fluorescence decay rate of 2 PJ 3 positronium (Ps) atoms [Γ fl] has been experimentally
determined using a Stark-mixing technique. Ground-state Ps atoms were optically excited in …

We describe the experimental production of a beam of 2 3 S 1 positronium (Ps) atoms
obtained from charge-exchange collisions between a positron beam and Xe held in a gas …

A muonium consists of a positive muon associated with an orbital electron, and the
spontaneous conversion to antimuonium serves as a clear indication of new physics beyond …

Laser spectroscopy of atomic hydrogen and hydrogen-like atoms is a powerful tool for tests
of fundamental physics. The 1 S–2 S transition of hydrogen in particular is a cornerstone for …

This paper presents a study of the passage of dimuonium through the foil of ordinary matter.
First, we provide an overview of how dimuonium is planned to be produced for such a type …

Positronium and muonium, as purely leptonic atoms without internal structure, provide ideal
systems for high-precision tests of quantum electrodynamics (QED) and measurements of …