Related papers: Model identification in $\mu^-\to e^-$ conversion …
We show asymptotic completeness of two-body scattering for a class of translation invariant models describing a single quantum particle (the electron) linearly coupled to a massive scalar field (bosons). Our proof is based on a recently…
We give an example of a purely bosonic model -- a rotor model on the 3D cubic lattice -- whose low energy excitations behave like massless U(1) gauge bosons and massless Dirac fermions. This model can be viewed as a ``quantum ether'': a…
The calculations entering the prediction of the standard model value for the anomalous magnetic moment of the muon $a_\mu$ are reviewed, and compared to the very accurate experimental measurement. The situation for the electron is discussed…
Non-unitarity of the neutrino mixing matrix is expected in many scenarios with physics beyond the Standard Model. Motivated by the search for deviations from unitary, we study two neutrino counting observables: the neutrino-antineutrino…
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…
In this report we will discuss properties of and models for nuclear transitions in muonic molecules formed via collisions of muonic atoms of hydrogen isotopes with light nuclei like $L\!i$ and $B\!e$. Their importance for nuclear…
We propose a fully flexible method to perform an hypothesis test between signal and background based on the Matrix Element Method in the presence of multiple invisible particles. The proposed method performs a mapping of the measured final…
We consider the transitions between electromagnetic bound states, such as the exclusive weak decay of a muonic atom into an electronic atom: $(\mu^- Z) \to (e^- Z) {\bar \nu_e }\nu_\mu . $ We show that relativistic effects in the atomic…
The flavor violating $\mu^--e^-$ conversion in nuclei is studied within the minimal supersymmetric standard model. We focus on the R-parity violating contributions at tree level including the trilinear and the bilinear terms in the…
A high-statistics determination of the differential cross section of elastic muon-electron scattering as a function of the transferred four-momentum squared, $d \sigma_{el}(\mu e \to \mu e)/dq^2$, has been argued to provide an effective…
Within the frame of LDM (light dark matter)-model, the LDM exchange particle $U$-boson (with mass 10-100 MeV) can be produced from many meson decay process so it attracts a lot of attention. Considering the merit of searching the $U$-boson…
The Standard Model prediction for the magnetic moment of the muon requires a determination of the electromagnetic form factor of the pion at high precision. It is shown that the recent progress in pi-pi scattering allows us to obtain an…
$\mu-e$ conversion is the experimentally most interesting lepton flavor violating process. From a theoretical point of view it is an interesting interplay of particle and nuclear physics. The effective transition operator, depending on the…
Within framework of the $\mu$ from $\nu$ Supersymmetric Standard Model ($\mu\nu$SSM), three exotic right-handed neutrino superfields induce new sources for lepton-flavor violation. In this work, we investigate muon conversion to electron in…
The spectrum of very fast electrons in five-lepton decay $\mu^+\to e^-e^+e^+\nu\bar\nu,$ that is the main background decay at the study of the muonium-antimuonium conversion in vacuum, is considered. The essential decrease of the spectral…
A model of photo-detection using a Bose--Einstein condensate in an atom-chip based micro trap is analyzed. Atoms absorb photons from the incident light field, receive part of the photon momentum and leave the trap potential. Upon counting…
This report is a primarily survey on the chemical nature of some exotic species containing the positively charged muon and the muonic Helium, i.e., the negatively charged muon plus helium nucleus, as exotic isotopes of hydrogen, using the…
Vector bosons, such as Dark Photon $A'$ or $Z'$, can couple to muons and be produced in the bremsstrahlung reaction $\mu^- + N \rightarrow \mu^- + N + A'(Z')$. Their possible subsequent invisible decay can be detected in fixed target…
The $L_{\mu}-L_{\tau}$ extension of the standard model predicts the existence of a lepton-flavor-universality-violating $Z^{\prime}$ boson that couples only to the heavier lepton families. We search for such a $Z^\prime$ through its…
In this paper I review a number of recent results in the field of exotic atoms. Recent experiments or ongoing experiments with muonic, pionic and antiprotonic hydrogen, as well as recent measurement of the pion mass are described. These…