Related papers: Predicting and Discovering True Muonium
The spectrum of electrons from muons decaying in an atomic bound state is significantly modified by their interaction with the nucleus. Somewhat unexpectedly, its first measurement, at the Canadian laboratory TRIUMF, differed from basic…
The recently proposed MUonE experiment at CERN aims at providing a novel determination of the leading order hadronic contribution to the muon anomalous magnetic moment through the study of elastic muon-electron scattering at relatively…
Since its inception, no decisive departure from the predictions of Standard Model (SM) has been reported. But recently various experiments have observed few hints of possible departure from SM predictions in lepton flavor universality…
The two-photon-annihilation contribution to the true muonium hyperfine splitting arising from $e$ and $\tau$ loops is obtained analytically at order $m_\mu\alpha^6$. The contribution to the hyperfine splitting is $-2.031092873…
The proposed fixed-target experiment, MUonE, at CERN will aim to measure the hadronic contribution to the running of the QED coupling by analysing the scattering of muons on electrons. Here we present state-of-the-art predictions for the…
From the comparison between the experimental and theoretical results for the energy difference between 2s1/2 and 2p1/2 states in hydrogen and hydrogen-like ions with different values of Z, we estimate bounds for the presence of an extra…
Laser spectroscopy of the Lamb shift (2S-2P energy difference) in light muonic atoms or ions, in which one negative muon $\mu^-$ is bound to a nucleus, has been performed. The measurements yield significantly improved values of the…
The potentiality of an experiment measuring the muon polarization in $K^+\rightarrow\pi^0\mu^+\nu_\mu$ at a $\phi$ factory is discussed, with particular attention to the possibility of revealing unexpected violation of Time reversal…
The energy levels of the $n=1$ and $n=2$ bound states of the $\mu^+\mu^-$ atom (true muonium) are calculated starting from a previously derived potential that correctly describes positronium to order $\alpha^5$ supplemented by the known…
We discuss the potential of long-baseline neutrino oscillation experiments to determine deviations from maximal \nu_\mu-\nu_\tau mixing. We compare the obtainable sensitivities to predictions from neutrino mass models and to the size of…
Motivated by the persisting 'anomaly' in the measurement of $P_5^\prime$, we review hadronic uncertainties entering the angular observables of the decay $\bar B\to {\bar K}^*\mu^+\mu^-$. We argue that hadronic uncertainties could account…
High precision spectroscopy can provide a sensitive tool to test Coulomb's law on atomic length scales. This can then be used to constrain particles such as extra "hidden" photons or minicharged particles that are predicted in many…
The Muon $g\textrm{-}2$ Experiment (E989) at Fermilab has a goal of measuring the muon anomaly ($a_\mu$) with unprecedented precision using positive muons. This measurement is motivated by the difference between the previous Brookhaven…
The decay Bs -> mu+mu- is very sensitive to contributions from new physics processes. Thus the Tevatron and LHC experiments are hunting for an observation of a Bs -> mu+mu- signal. In this article the updated search for Bs -> mu+mu- and B0…
The recent measurement of the muon anomalous magnetic moment by the Fermilab E989 experiment, when combined with the previous result at BNL, has confirmed the tension with the SM prediction at $4.2\,\sigma$ CL, strengthening the motivation…
The muon anomaly $a_\mu=(g_\mu-2)/2$ showing a persisting 3 to 4 $\sigma$ deviation between the SM prediction and the experiment is one of the most promising signals for physics beyond the SM. As is well known, the hadronic uncertainties…
The MUonE experiment has been proposed to measure the differential cross section of $\mu e$ elastic scattering, by colliding the 160 GeV muons of the CERN M2 beam with atomic electrons of thin target plates. From a very precise measurement…
The search for lepton flavour violation in charged lepton decays is highly sensitive to physics beyond the Standard Model. Among the possible processes, $\mu$-decays are considered to have the largest discovery potential in most of the…
The 3.6 \sigma discrepancy between the predicted and measured values of the anomalous magnetic moment of positive muons can be explained by the existence of a new dark boson Z_\mu with a mass in the sub-GeV range, which is coupled…
This talk discusses possible new physics interpretations of recent experimental results on the B-->K*mu+mu- decay that show a discrepancy with the Standard Model predictions. A model independent analysis that takes into account all the…