Related papers: Muon Decay Spectrum: Leading Logarithmic Approxima…
Recoil corrections to the atomic decay rate are considered in the order of Zm/M . The expressions are treated exactly without any expansion over Z alpha. The expressions obtained are valid both for muonic atoms (for which they contribute on…
Instability of the excitation spectrum of an ordered noncollinear Heisenberg antiferromagnet (AF) with respect to spontaneous two-magnon decays is investigated. We use a spin-1/2 AF on a triangular lattice as an example and examine the…
The limits on lepton radii and contact interaction scales are used to derive limits on the deviations of lepton anomalous magnetic dipole moments (g-2)/2 from the Standard Model predictions. In the case of quadratic dependence of the…
We consider quantum electrodynamics (QED) corrections to the fine splitting $E(2P_{3/2}) - E(2P_{1/2})$ in the Li atom. We derive complete formulas for the $m\,\alpha^6$ and $m\,\alpha^7\,\ln\alpha$ contributions and calculate them…
The muon energy spectra of the quasi-elastic and 1-pion production events in a LBL experiment, like K2K, are predicted to follow closely the neutrino energy spectrum, with downward shifts of the energy scale by $<Q^2>/2 M$ and $(<Q^2> +…
In this contribution, we present recent progress from the RBC/UKQCD collaboration on the first calculation of the long-distance two-photon contribution to the decay amplitude of a long-lived kaon into a pair of charged muons.
The largest contributions to the $n=2$ Lamb-shift, fine structure interval and $2s$ hyperfine structure of muonic hydrogen are calculated by exact numerical evaluations of the Dirac equation, rather than by a perturbation expansion in…
We calculate the corrections of orders alpha^3, alpha^4 and alpha^5 to the Lamb shift of the 1S and 2S energy levels of muonic hydrogen (mu p) and muonic deuterium (mu d). The nuclear structure effects are taken into account in terms of the…
The current experimental values of anomalous magnetic moments of muon and electron deviate from the Standard Model predictions by few standard deviations, which might be a hint of new physics. The sizes and signs of these deviations are…
We consider $K_{l2}$ decays to the order $O(\alpha)$. We perform a matching calculation, using a specific model with vector meson dominance in the long distance part and the parton model in the short distance part. By considering the…
A theoretical description of elastic polarized muon-electron scattering is presented. Complete one-loop electroweak radiative corrections are calculated with taking into account the exact dependence on the muon mass. The effects due to some…
Searches for new physics using muons are reviewed. Particular attention is paid to muon number non-conserving processes, like the decay muon-->e+gamma and muon-electron conversion in muonic atoms. Also, experimental determinations and…
We employ an effective Lagrangian approach to derive the leading-logarithm two-loop electroweak contributions to the muon anomalous magnetic moment, a_mu. We show that these corrections can be obtained using known results on the anomalous…
The contributions to the g-2 of the muon from some tenth-order (five-loop) graphs containing one-loop and two-loop vacuum polarization insertions have been evaluated analytically in QED perturbation theory, expanding the results in the…
We calculate the QED and QCD radiative corrections to the charged lepton energy distributions in the dominant semileptonic decays of the top quark $t \to b W^+ \to b(\ell^+ \nu_\ell)$ $(\ell=e, \mu, \tau)$ in the standard model(SM), and for…
We calculate the next-to-next-to-leading order QCD corrections to the leptonic invariant mass ($q^2$) spectrum of semileptonic $b \to c$ inclusive decays, taking into account the mass of the charm quark and the charged lepton in the final…
We present a summary of the results of two recent precise calculations of the muon anomalous magnetic moment ($g_{\mu}-2$) and the electromagnetic coupling on the $Z$ ($\bar{\alpha}_{\rm Q.E.D.}(M^2_{Z})$). The main sources of uncertainty…
In this talk I report on the results of a complete O(\alpha) calculation of leptonic \mu-decay. The calculation is complete in the sense that all polarization and mass effects have been included in the radiative corrections. I mostly…
After presenting a survey of theoretical results concerning the structure of two-dimensional QCD, we present a numerical study related to the mass eigenstates and the decay amplitudes of higher mesonic states. We discuss in detail the fate…
Order \alpha^2 corrections to the decay rate of orthopositronium are calculated in the framework of nonrelativistic QED. The resulting contribution is found to be in significant disagreement with one set of experimental measurements though…