Related papers: Increased Sensitivity to Possible Muonium to Antim…
The muonium-to-antimuonium transition experiment is about to be updated. Notably, the experiment at J-PARC in Japan can explore the magnetic field dependence of the transition probability. In this paper, we investigate the information that…
The Mu2e experiment searches for the neutrino-less muon to electron conversion in the field of a nucleus, which is a charged lepton flavor violating process. The goal of the experiment is to reach a single event sensitivity of 2.8 x…
The muon g-2 collaboration has measured the anomalous magnetic g value of the positive muon to within a relative uncertainty of 0.7 parts per million. The result, a_{\mu^+} = 11 659 204(7)(5) x 10^{-10} is in good agreement with the…
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 the Standard Model in particle physics.One of the most important…
We present a new experiment, Mu-MASS, aiming for a 1000-fold improvement in the determination of the 1S-2S transition frequency of Muonium (M), the positive-muon/electron bound state. This substantial improvement beyond the current…
The anomalous magnetic moment of the negative muon has been measured to a precision of 0.7 parts per million (ppm) at the Brookhaven Alternating Gradient Synchrotron. This result is based on data collected in 2001, and is over an order of…
This letter reports results from a search for muon-neutrino to electron-neutrino transitions by the MINOS experiment based on a 7x10^20 protons-on-target exposure. Our observation of 54 candidate electron-neutrino events in the Far Detector…
We study muonium-antimuonium conversion and mu+ e- to mu- e+ scattering within two different lepton-flavor-violating models with heavy neutrinos: model I is a typical seesaw that violates lepton number as well as flavor; model II has a…
The status of the muon (g-2) experiment at the Brookhaven AGS is reviewed. An accuracy of 1.3 ppm on the mu^+ anomalous magnetic moment has been achieved and published. This result differs with the standard model prediction by about 2.5…
The COMET experiment at J-PARC, Japan, aims to search for muon to electron conversion with aluminium nuclei, achieving a sensitivity four orders of magnitude higher than the current upper limit at a 90% confidence level. The proton beam…
The Mu2e experiment at Fermilab will search for the neutrinoless $\mu^- \to e^-$ conversion in the field of an aluminum nucleus. The Mu2e data-taking plan assumes two running periods, Run I and Run II, separated by an approximately…
In their 2006 paper setting the current limit on \mumemconv\ conversion search on a gold target \cite{sindrum_ii:Bertl2006}, the SINDRUM-II collaboration published, along with the electron momentum distribution, the momentum distribution of…
A new measurement of the anomalous magnetic moment of the muon, $a_{\mu} \equiv (g-2)/2$, will be performed at the Fermi National Accelerator Laboratory with data taking beginning in 2017. The most recent measurement, performed at…
We review the theory of the Lamb shift for muonium, provide an updated numerical value and present the prospects of the Mu-MASS collaboration at PSI to improve upon their recent measurement. Due to its smaller nuclear mass, the…
In the Standard Model there are several canonical examples of pure leptonic processes involving the muon, the electron and the corresponding neutrinos which are connected by the crossing symmetry: i) the decay of muon, ii) the inverse muon…
A new measurement of the magnetic anomaly $a_{\mu}$ of the positive muon is presented based on data taken from 2020 to 2023 by the Muon $g-2$ Experiment at Fermi National Accelerator Laboratory (FNAL). This dataset contains over 2.5 times…
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 experimental discovery of large nu_mu-nu_tau mixing indicates that analogous mixing in the charged lepton sector could be substantial. We consider the possibility that if a high intensity muon beam, perhaps at the early stages of a muon…
The E989 Muon $g-2$ Experiment at Fermilab aims to measure the muon magnetic anomaly, $a_\mu$, to an unprecedented precision of 140 parts per billion (ppb), representing a four-fold improvement over the current best measurement, achieved at…
The Muon (g-2) Experiment (E821) at Brookhaven National Laboratory (BNL) has measured the anomalous magnetic moment of the positive muon to an unprecedented precision of 1.3 parts per million. The result, a_{\mu^+} = (g-2)/2 = 11 659…