Related papers: Muonium
A positive muon ($\mu^+$) and an electron ($e^-$) form the the hydrogen-like muonium atom ($M$=$\mu^+ e^-$). Since it consists of two leptonic particles which are according to present knowledge point-like, accurate calculations of its level…
The hydrogen-like muonium atom ($\mu^+e^-$) consists of a positive muon ($\mu^+$) and an electron ($e^-$). Since it was first observed by Hughes et al. in 1960, a series of precision experiments could be carried out testing bound state…
The muonium atom is the purely leptonic bound state of a positive muon and an electron. It has a lifetime of 2.2 $\mu$s. The absence of any known internal structure provides for precision experiments to test fundamental physics theories and…
We consider the most accurate tests of bound state QED, precision theory of simple atoms, related to the hyperfine splitting in light hydrogen-like atoms. We discuss the HFS interval of the 1s state in muonium and positronium and of the 2s…
The electromagnetic interactions of electrons and muons can be described to very high accuracy within the framework of standard theory, in particular within the hydrogen-like muonium atom. Therefore precision measurements allow to test…
The observed interactions between particles are not fully explained in the successful theoretical description of the standard model to date. Due to the close confinement of the bound state muonium ($M = \mu^+ e^-$) can be used as an ideal…
We consider the most accurate tests of bound state QED theory of the hyperfine splitting in two-body atoms related to the HFS interval of the 1s state in muonium and positronium and the 2s state in hydrogen, deuterium and the helium-3 ion.…
Electroweak second order shifts of muonium ($\mu^+e^-$ bound state) energy levels are calculated for the first time. Calculation starts from on-shell one-loop elastic $\mu^+ e^-$ scattering amplitudes in the center of mass frame, proceed to…
Total energies and various bound state properties are determined for the ground states in all six four-body muonic $a^{+} b^{+} \mu^{-} e^{-}$ quasi-atoms. These quasi-atoms contain two nuclei of the hydrogen isotopes $p^{+}, d^{+}, t^{+}$,…
The purpose of this article is twofold. First, we attempt to give a brief overview of the different application areas of quantum electrodynamics (QED). These include fundamental physics (prediction of atomic energy levels), where the atom…
This review is devoted to precision physics of simple atoms. The atoms can essentially be described in the framework of quantum electrodynamics (QED), however, the energy levels are also affected by the effects of the strong interaction due…
Bound muons (also pions, kaons, etc) increase the fission barrier and produce some stabilizing effects for highly charged nuclei. If the binding energy of the muon exceeds $mc^2$, it becomes stable. The $1s$ state of a muon inside an exotic…
Some recent precision experiments in low energy muon physics are discussed. Spectroscopy on the muonium atom, the bound state of a positve muon and an electron, has provided precise tests of standard theory and yielded most precise values…
The first fully relativistic, rigorous QED calculations of the self-energy correction to the fine-structure levels of heavy muonic atoms are reported. We discuss nuclear model and parameter dependence for this contribution as well as…
A hydrogen-like atom consisting of a positive muon and an electron is known as muonium. It is a near-ideal two-body system for a precision test of bound-state theory and fundamental symmetries. The MuSEUM collaboration performed a new…
Recent progress in laser and x-ray spectroscopy of muonic atoms offers promising long-term possibilities at the intersection of atomic, nuclear and particle physics. In muonic hydrogen, laser spectroscopy measurements will determine the…
We review the status of the QED calculations for the muonium $2S_{1/2}-2P_{3/2}$ energy interval and provide the updated theoretical value of $9874.357\pm0.001\,\mathrm{MHz}$. Additionally, we present a model for probing Lorentz-violating…
We study hydrogen-like atoms in N=1 supersymmetric quantum electrodynamics with an electronic and a muonic family. These atoms are bound states of an anti-muon and an electron or their superpartners. The exchange of a photino converts…
Fundamental physics could be described as having a muon problem. Discrepancies between theory and experiment in a number of muonic measurements ($r_P$, $a_\mu$, $H\rightarrow\mu\tau$, $\mathcal{R}_K$, $\mathcal{R}_{D^*}$) have been observed…
Energy levels of a two-body atomic system in an external homogeneous magnetic field can be presented in terms of magnetic moments of their components, however, those magnetic moments being related to bound particles differ from their free…