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Related papers: Muon Decay Spectrum: Leading Logarithmic Approxima…

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The semileptonic B-> Xu l nu decays allow a pretty clean determination of the CKM matrix element |Vub|. Nevertheless, the presence of weak-annihilation effects near the end-point of the q2 spectrum introduces uncertainties in the inclusive…

High Energy Physics - Phenomenology · Physics 2008-11-26 J. J. Sanz-Cillero

We consider three-loop radiative-recoil corrections to hyperfine splitting in muonium. These corrections are enhanced by the large logarithm of the electron-muon mass ratio. The leading logarithm cubed and logarithm squared contributions…

High Energy Physics - Phenomenology · Physics 2009-11-10 Michael I. Eides , Howard Grotch , Valery A. Shelyuto

The pure lepton decay of the polarized muon is considered, accounting for a new tensor interaction which is outside of the Michel local interactions. This interaction leads to new energy distribution and polarization of the final charged…

High Energy Physics - Phenomenology · Physics 2007-05-23 M. V. Chizhov

The muon anomalous $g$ value, $a_\mu=(g-2)/2$, is calculated up to one-loop level in noncommutative QED. We argue that relativistic muon in E821 experiment nearly always stays at the lowest Landau level. So that spatial coordinates of muon…

High Energy Physics - Theory · Physics 2009-11-07 Xiao-Jun Wang , Mu-Lin Yan

We have previously analysed the chiral predictions for the decay K_L -> pi0 gamma e+ e- and discussed how experimental measurements of this process can help our understanding of chiral theories and of CP tests. Motivated by the possibility…

High Energy Physics - Phenomenology · Physics 2009-10-31 John F. Donoghue , Fabrizio Gabbiani

The theoretical status of the muon anomaly is reviewed including the recent change in the light by light hadronic correction. Specific attention is given to the implications of the shift in the difference between the BNL experimental result…

High Energy Physics - Phenomenology · Physics 2009-11-07 Utpal Chattopadhyay , Achille Corsetti , Pran Nath

We use the Mellin-Barnes representation in order to improve the theoretical estimate of mass corrections to the width of light pseudoscalar meson decays into a lepton pair, $P\to l^{+}l^{-}$ . The full resummation of the terms…

High Energy Physics - Phenomenology · Physics 2009-06-19 A. E. Dorokhov , M. A. Ivanov , S. G. Kovalenko

This article reviews and updates the Standard Model prediction of the muon g-2. QED, electroweak and hadronic contributions are presented, and open questions discussed. The theoretical prediction deviates from the present experimental value…

High Energy Physics - Phenomenology · Physics 2009-07-09 M. Passera

The partial decay rate $\Gamma(Z\to b\bar{b})$ is significantly influenced by the mass of the top quark due to electroweak radiative corrections. The leading $\sim m_t^2$ and the next-to-leading contribution $\sim \ln m_t^2$ are known to be…

High Energy Physics - Phenomenology · Physics 2011-04-20 A. Kwiatkowski , M. Steinhauser

The angular distributions and the differential branching fraction of the decay B0 to K*(892)0 mu+ mu- are studied using a data sample corresponding to an integrated luminosity of 5.2 inverse femtobarns collected with the CMS detector at the…

High Energy Physics - Experiment · Physics 2013-11-11 CMS Collaboration

This talk summarizes the recent developments in the evaluation of the leading order hadronic contributions to the running of the QED fine structure constant $\alpha(s)$, at $s=M_{\rm Z}^2$, and to the anomalous magnetic moment of the muon…

High Energy Physics - Phenomenology · Physics 2009-10-31 Michel Davier

We calculate (g-2)/2 of the muon, by improving the determination of the hadronic vacuum polarisation contribution, a_mu^{had,LO}, and its uncertainties. The different e+e- data sets for each exclusive (and the inclusive) channel are…

High Energy Physics - Phenomenology · Physics 2008-11-26 K. Hagiwara , A. D. Martin , Daisuke Nomura , T. Teubner

Details of a recent calculation of O(alpha_s^2) corrections to the decay b -> c,l,nu_l, taking into account the c-quark mass, are described. Construction of the expansion in the mass ratio m_c/m_b as well as the evaluation of new four-loop…

High Energy Physics - Phenomenology · Physics 2008-12-30 Alexey Pak , Andrzej Czarnecki

The angular distributions and the differential branching fraction of the decay B0 to K*0(892) mu mu are studied using data corresponding to an integrated luminosity of 20.5 inverse femtobarns collected with the CMS detector at the LHC in pp…

High Energy Physics - Experiment · Physics 2015-12-31 CMS Collaboration

A recently proposed experiment, MUonE, aims to extract the hadronic vacuum polarisation contribution to the muon g-2 from muon-electron scattering at low energy. The extrapolation requires that both experimental and theoretical…

High Energy Physics - Phenomenology · Physics 2023-09-13 Marco Rocco

We study the systematic inclusion of QED corrections in the evolution of parton distributions. O(alpha) corrections modify the evolution equation for parton distributions. They introduce additional parton distributions, like the photon…

High Energy Physics - Phenomenology · Physics 2014-11-17 Markus Roth , Stefan Weinzierl

Any theory that have a global spontaneously broken symmetry will imply the existence of very light neutral bosons or massless bosons (sometimes called Majorons). For most of these models we have neutrino-Majoron couplings, that appear as…

High Energy Physics - Phenomenology · Physics 2008-11-26 A. P. Lessa , O. L. G. Peres

The results of a recent next-to-leading order QCD analysis of the world data on polarized deep inelastic scattering are reported. New parameterizations are derived for the quark and gluon distributions and the value of $\alpha_s(M_z^2)$ is…

High Energy Physics - Phenomenology · Physics 2010-11-19 Johannes Blümlein , Helmut Böttcher

Transition rates for coherent muon-electron conversion in muonic atoms, mu+N --> e+N, are computed for various types of muon number violating interactions. Attention is paid to relativistic atomic effects, Coulomb distortion, finite nuclear…

High Energy Physics - Phenomenology · Physics 2009-10-31 Andrzej Czarnecki , William J. Marciano , Kirill Melnikov

The energy spectra of spin-1/2 electrons under two-dimensional magnetic field modulations are calculated beyond the one-band approximation. Our formulation is generally applicable to a modulation field with a rectangular lattice symmetry.…

Mesoscale and Nanoscale Physics · Physics 2007-05-23 Ming-Che Chang , Min-Fong Yang