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Related papers: On the QED Radiator at Order $\alpha^3$

200 papers

The effect of the collinear photon radiation by charged particles is considered in the second order of the perturbation theory. Double and single photon radiation is evaluated. The corresponding radiation factors are obtained. The QED…

High Energy Physics - Phenomenology · Physics 2008-11-26 A. B. Arbuzov , E. S. Scherbakova

We derive QED radiators for the universal corrections to polarized electron scattering. To 5th order in the coupling constant the flavor non-singlet and singlet contributions are calculated. We derive the non-singlet and singlet…

High Energy Physics - Phenomenology · Physics 2007-05-23 J. Blümlein , H. Kawamura

We calculate the universal flavor-singlet radiative QED corrections to unpolarized lepton scattering applicable to general differential scattering cross sections, involving charged fermions or photons in initial or final states. The…

High Energy Physics - Phenomenology · Physics 2008-11-26 Johannes Blümlein , Hiroyuki Kawamura

We describe a simplified derivation for the relativistic corrections of order $\alpha^4$ for a bound system consisting of two spinless particles. We devote special attention to pionium, the bound system of two oppositely charged pions. The…

High Energy Physics - Phenomenology · Physics 2009-11-07 U. D. Jentschura , G. Soff , P. J. Indelicato

We compute O(alpha^3 ln alpha) relative corrections to the ground state hyperfine splitting of a QED two body bound state with different masses of constituents. The general result is then applied to muonium and positronium. In particular, a…

High Energy Physics - Phenomenology · Physics 2009-10-31 Kirill Melnikov , Alexander Yelkhovsky

We compute O(alpha^3 ln alpha) corrections to the decay rates of para- and orthopositronium into two and three photons, respectively. For this calculation we employ the nonrelativistic QED regularized dimensionally and we explain how in…

High Energy Physics - Phenomenology · Physics 2009-10-31 Kirill Melnikov , Alexander Yelkhovsky

In this paper, the nonfactorizable photonic corrections to the effective four-fermion vertex for the $\overline{B}$ ${\to}$ $D^{({\ast})}$ $+$ ${\ell}^{-}$ $+$ $\bar{\nu}_{\ell}$ decays are considered at the quark level within SM, where…

High Energy Physics - Phenomenology · Physics 2024-12-11 Yueling Yang , Liting Wang , Jiazhi Li , Qin Chang , Junfeng Sun

O(\alpha) QED radiative corrections to polarized neutral current leptoproduction of heavy quark flavours are calculated in the leading log approximation for HERMES, COMPASS, and HERA kinematics. Besides the inclusive case, we derive general…

High Energy Physics - Phenomenology · Physics 2009-10-30 I. Schienbein

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…

High Energy Physics - Phenomenology · Physics 2014-11-20 Ahmed Ali , Eduard A. Kuraev , Yury Bystritskiy

We calculate the next-to-next-to-leading order ${\cal O}(\alpha_s^4)$ one-loop squared corrections to the production of heavy quark pairs in quark-antiquark annihilations. These are part of the next-to-next-to-leading order ${\cal…

High Energy Physics - Phenomenology · Physics 2008-11-26 J. G. Körner , Z. Merebashvili , M. Rogal

The velocity renormalization group is used to determine ln(alpha) contributions to QED bound state energies. The leading order anomalous dimension for the potential gives the alpha^5 ln(alpha) Bethe logarithm in the Lamb shift. The…

High Energy Physics - Phenomenology · Physics 2009-10-31 Aneesh V. Manohar , Iain W. Stewart

The $O(\alpha^2\log(Q^2/m_e^2))$ leptonic QED corrections to unpolarized deeply inelastic electron-nucleon scattering are calculated in the mixed variables.

High Energy Physics - Phenomenology · Physics 2007-05-23 J. Blümlein , H. Kawamura

After 10 years of steadily increasing the experimental precision at LEP/SLC, there is a strong demand on an update of existing programs for fermion pair production. We present a rederivation of the O(alpha) Bremsstrahlung corrections to…

High Energy Physics - Phenomenology · Physics 2007-05-23 M. Jack

The ${\cal O}(\alpha)$ radiative corrections to the process $p\,p\hskip-7pt\hbox{$^{^{(\!-\!)}}$} \rightarrow \gamma^*, \, Z \rightarrow \ell^+ \ell^-$ ($\ell=e,\,\mu$) are calculated. Factorizing the collinear singularity associated with…

High Energy Physics - Phenomenology · Physics 2009-10-30 U. Baur , S. Keller , W. K. Sakumoto

A general method for computing ${\cal O} (\alpha^2)$ and higher-order next-to-leading photonic corrections is presented and applied to the precision calculation of the small-angle Bhabha scattering cross section in the phase-space region of…

High Energy Physics - Phenomenology · Physics 2011-04-20 G. Montagna , O. Nicrosini , F. Piccinini

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…

High Energy Physics - Phenomenology · Physics 2011-07-19 G. Degrassi , G. F. Giudice

The $O(\alpha)$ leptonic QED corrections to neutral current polarized deep inelastic lepton-nucleon scattering are calculated in leptonic variables both for the case of longitudinal and transverse nucleon polarization. The results of the…

High Energy Physics - Phenomenology · Physics 2009-10-30 D. Bardin , J. Blümlein , P. Christova , L. Kalinovskaya

We consider excited lepton ($\bar{l^*}l {\rm or} \bar{l^*}l^*$) production in the context of effective theories with being four-fermion contact interaction at LHC. We also consider the two body decay mode of excited lepton ($l^*$) to…

High Energy Physics - Phenomenology · Physics 2015-03-10 Swapan Majhi

We compute the order-$\as$ corrections to the total cross section and to jet rates for the process $\epem\to\epem +$ hadrons, where the hadrons are produced through crossed-channel quark exchange in the hard scattering of two off-shell…

High Energy Physics - Phenomenology · Physics 2009-10-31 M. Cacciari , V. Del Duca , S. Frixione , Z. Trocsanyi

The $O(\alpha)$ corrections to $\gamma\gamma --> f \bar f$ in the Standard Model are calculated for arbitrary, light fermions $f$. The relevant analytical results are listed in a form that is appropriate for practical applications, and…

High Energy Physics - Phenomenology · Physics 2008-11-26 A. Denner , S. Dittmaier