Related papers: Three-Loop Contributions to Hyperfine Splitting: M…
We present a new strategy for the dispersive evaluation of the hadronic light-by-light contribution to the anomalous magnetic moment of the muon $a_\mu$. The new approach directly applies in the kinematic limit relevant for $a_\mu$: one of…
Recent results of two interesting classes of supersymmetric two-loop contributions to (g-2)_mu are presented. Two-loop diagrams involving a closed sfermion loop can amount to 5*10^{-10} or almost one standard deviation of the current…
Using data collected with the L3 detector near the Z resonance, corresponding to an integrated luminosity of 150pb-1, the branching fractions of the tau lepton into electron and muon are measured to be B(tau->e nu nu) = (17.806 +- 0.104…
We present the QCD and QED corrections to the fermion-loop contributions to light-by-light scattering, gamma gamma to gamma gamma, in the ultrarelativistic limit where the kinematic invariants are much larger than the masses of the charged…
Differential and integral cross sections of the muon are calculated in the materials: water, standard rock, iron and lead with and without the LPM effect. The corresponding cross sections are also calculated with dielectric supression…
The anomalous magnetic moment of muon, $g-2$, is a very precisely measured quantity. However, the current measurement disagrees with standard model by about 3 standard deviations. Hadronic vacuum polarization and hadronic light by light are…
We compute the contributions to continuum photon pair production at hadron colliders from processes initiated by gluon-gluon and gluon-quark scattering into two photons through a four-leg virtual quark loop. Complete two-loop cross sections…
We present a lattice calculation of the leading order (LO) hadronic vacuum polarization (HVP) contribution to the muon anomalous magnetic moment for the connected light and strange quarks, $a^{\rm W}_{{\rm con}, l/s}$ in the widely used…
We present the analytic expressions of the three-loop virtual corrections to the helicity amplitudes of 2 -> 2 four-fermion scattering processes in massless QED. The contributing Feynman diagrams are grouped into integrand families…
We present the results of analytical calculations of the 3-loop contributions to the asymptotic photon vacuum polarization function, in the on shell scheme, and of the 4-loop contributions to the on shell QED beta-function. These are used…
The rigorous calculation of the vacuum-polarization screening corrections to the hyperfine splitting in Li-like bismuth is presented. The two-electron diagrams with electric and magnetic vacuum-polarization loops are evaluated to all orders…
We compute three-loop corrections to the process $gg\to HH$ originating from one-particle reducible diagrams. This requires the computation of two-loop corrections to the gluon-gluon-Higgs vertex with an off-shell gluon. We describe in…
The short-distance coefficients for the color-octet ^3S_1 term in the fragmentation function for a gluon to split into polarized heavy quarkonium states are re-calculated to order alpha_s^2. The light-cone gauge remarkably simplifies the…
Contributions of a spin 0 axion-like particle (ALP) to lepton dipole moments, g-2 and EDMs, are examined. Barr-Zee and light-by-light loop effects from a light pseudoscalar ALP are found to be capable of resolving the long-standing muon g-2…
We present results for single pseudoscalar meson pole contributions and pion box contributions to the hadronic light-by-light (LBL) correction of the muon's anomalous magnetic moment. We follow the recently developed dispersive approach to…
We present a reliable nonperturbative calculation of the QCD correction, at leading order in the electromagnetic coupling, to the anomalous magnetic moment of the electron, muon, and tau leptons using two-flavor lattice QCD. We use multiple…
We present a preliminary lattice calculation of the leading-order electromagnetic and strong isospin-breaking corrections to the Hadronic Vacuum Polarization (HVP) contribution of the light quarks to the anomalous magnetic moment of the…
We present new results for the light-quark connected part of the leading order hadronic-vacuum-polarization (HVP) contribution to the muon anomalous magnetic moment, using $2+1+1$ staggered fermions. We have collected more statistics on…
We systematically compute and discuss meson and muon polarized radiative decays. Doubly differential distributions in terms of momenta and helicities of the final lepton and photon are explicitly computed. The undergoing dynamics giving…
We present a lattice calculation of the Hadronic Vacuum Polarization (HVP) contribution to the anomalous magnetic moments of the electron, $a_e^{\rm HVP}$, the muon, $a_\mu^{\rm HVP}$, and the tau, $a_\tau^{\rm HVP}$, including both the…