相关论文: Discovering True Muonium in $K_L\rightarrow (\mu^+…
Rare meson decay experiments promise to measure branching ratios as small as $10^{-13}$. This presents an opportunity to discover the $\mu^+\mu^-$ bound state true muonium. We consider a set of possible channels, all with branching ratios…
The recent observation of discrepancies in the muonic sector motivates searches for the yet undiscovered atom true muonium $(\mu^+\mu^-)$. To leverage potential experimental signals, precise theoretical calculations are required. I will…
We report on a measurement of the decay $K_L\rightarrow\mu^+\mu^-\gamma$ from Fermilab experiment E799. We observe $207$ candidate signal events with an estimated background of $10.5 \pm 4.0$ events and establish…
We find that the normal muon polarization in the decay K->mu nu_mu gamma is very sensitive to the values of the kaon vector F_V and axial-vector F_A form factors. It is shown that the ongoing KEK-E246 experiment can definitely determine the…
We study the potential of the LHCb experiment to discover, for the first time, the $\mu^+\mu^-$ true muonium bound state. We propose a search for the vector $1^3S_1$ state, $\mathcal{T\!M}$, which kinetically mixes with the photon and…
True muonium, the bound state of a muon and an antimuon ($\mu^+\mu^-$), has long been theoretically predicted but remains experimentally elusive. We investigate the production of true para-muonium in the radiative decay of $J/\psi$…
We have observed the decay $K_L\to \mu^+\mu^- \gamma \gamma$ at the KTeV experiment at Fermilab. This decay presents a formidable background to the search for new physics in $K_L\to\pi^0\mu^+\mu^-$. The 1997 data yielded a sample of 4…
Motivated by new precise results on several $K_L$ decays, sensitive to the ${K_L \to \gamma \gamma}$ form factor, we present a new analysis of the $K_L\to \mu^+\mu^-$ long-distance amplitude based on a semi-phenomenological approach.…
We present a comprehensive calculation of the $K_L\to\gamma^*\gamma^*$ form factor in dispersion theory, using input from the leptonic decays $K_L\to\ell^+\ell^-\gamma$, $K_L\to \ell_1^+\ell_1^-\ell_2^+\ell_2^-$, the hadronic mode $K_L\to…
Evidence of the $K^+\to\mu^+\nu\bar\nu\nu$ decay was searched for using E949 experimental data with an exposure of $1.70\times 10^{12}$ stopped kaons. The data sample is dominated by the backgrond process $K^+\to\mu^+\nu_\mu\gamma$. An…
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…
We find that the phase appearing in the unitarity relation between $\mathcal{B}(K_L\rightarrow \mu^+\mu^-)$ and $\mathcal{B}(K_L\rightarrow \gamma\gamma)$ is equal to the phase shift in the interference term of the time-dependent…
Upcoming fixed-target experiments designed to search for new sub-GeV forces will also have sensitivity to the never before observed True Muonium atom, a bound state of a muon and anti-muon. We describe the production and decay…
We analyze $K_L$ lepton pair decays of $K_L \to l^+\l^-\gamma$ and $K_L \to l^+l^-l'^+l'^-$ $(l, l'=e, \mu)$ within the framework of the light-front QCD approach (LFQA). With the $K_L \to \gamma^* \gamma^*$ form factors evaluated in a model…
Measuring the muon anomalous magnetic moment g-2 and the rare decays of light pseudoscalar mesons into lepton pair P \to l+l- serve as important test of the standard model. To reduce the theoretical uncertainty in the standard model…
True muonium ($\mu^+\mu^-$) is one of the heaviest and smallest electromagnetic bound states not containing hadrons, and has never been observed so far. In this work it is shown that the spin-1 TM state (ortho-TM) can be observed at a…
We studied the radiative muon decay $\mu^+ \to e^+\nu\bar{\nu}\gamma$ by using for the first time an almost fully polarized muon source. We identified a large sample (~13000) of these decays in a total sample of 1.8x10^14 positive muon…
True muonium ($\mu^+\mu^-$) is one of the cleanest bound states, being composed only of leptons, along with true tauonium and positronium. Unlike the latter, true muonium and true tauonium have not been observed so far. This article shows…
We investigate the production of the as-yet-undetected true muonium within the quark-gluon plasma formed in relativistic heavy-ion collisions, employing a relativistic Boltzmann transport framework coupled to viscous hydrodynamic…
This year, LHC provided a very stringent bound on Br(Bs->mu+mu-), bringing it closer to the value predicted by the Standard Model (SM). Bs->mu+mu- was believed to be the golden mode at LHCb to find SUSY because a large enhancement was…