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Related papers: QCD Corrections to $\Delta\rho$

200 papers

We calculate the leading-logarithmic and next-to-leading-logarithmic electroweak corrections to the charm-top-quark contribution to the effective $|\Delta S| = 2$ Lagrangian, relevant for the parameter $\epsilon_K$. We find that these…

High Energy Physics - Phenomenology · Physics 2022-12-12 Joachim Brod , Sandra Kvedaraite , Zachary Polonsky , Ahmed Youssef

The QCD radiative corrections to the leptonic decay rate of the $B_c$ meson are calculated using the formalism of nonrelativistic QCD (NRQCD) to separate short-distance and long-distance effects. The $B_c$ decay constant is factored into a…

High Energy Physics - Phenomenology · Physics 2009-10-28 Eric Braaten , Sean Fleming

We calculate the branching ratio for B -> J/psi + anything, within the color-singlet approximation for J/psi production, but including perturbative QCD corrections beyond the leading logarithm approximation. Such higher order corrections…

High Energy Physics - Phenomenology · Physics 2009-10-30 Joao M. Soares , Tibor Torma

We compute B->K eta' branching ratio using perturbative QCD approach. We show that a triangular relation among amplitudes for B^0->K^0 pi^0, B^0->K^0 eta, B^0->K^0 eta' receives large corrections from SU(3) breaking effects. If experimental…

High Energy Physics - Phenomenology · Physics 2009-11-07 E. Kou , A. I. Sanda

The self-energy and vertex QED radiative corrections to the parity nonconservation (PNC) amplitude in atoms are obtained using the perturbation theory in powers of (alpha Z). The calculated linear in (alpha Z) term gives -0.6 % for the PNC…

High Energy Physics - Phenomenology · Physics 2009-11-07 M. Yu. Kuchiev

It is demonstrated how perturbative O(alpha_s^2) relativistic corrections to the non-relativistic stable heavy quark-antiquark production cross section in e^+e^- annihilation based on a Coulombic QCD potential can be systematically…

High Energy Physics - Phenomenology · Physics 2014-11-17 A. H. Hoang

We calculate the full one-loop electroweak radiative corrections, of ${\cal O}(\alpha^2\alpha_s)$, to the cross section of single $Z$-boson inclusive hadroproduction at finite transverse momentum ($p_T$). This includes the ${\cal…

High Energy Physics - Phenomenology · Physics 2015-12-09 W. Hollik , B. A. Kniehl , E. S. Shcherbakova , O. L. Veretin

The cross-section for ZZ->ZZ with arbitrarily polarized Z bosons is calculated within the electroweak Standard Model including the complete O(alpha) corrections. We show the numerical importance of the radiative corrections and elaborate…

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

The perturbative quark-mass corrections to the $\tau$ hadronic width are analysed to $O(\alpha_s^3 m_q^2)$, using the presently available theoretical information. The behaviour of the perturbative series is investigated in order to assess…

High Energy Physics - Phenomenology · Physics 2010-02-03 Antonio Pich , Joaquim Prades

We present the (two--loop) QCD corrections to the longitudinal and transverse components of the electroweak gauge bosons self--energies for arbitrary momentum transfer and for different internal quark masses. Compact formulae for both the…

High Energy Physics - Phenomenology · Physics 2014-11-17 A. Djouadi , P. Gambino

We study the scheme dependence of the two-loop expression for the $\rho$-parameter of the Standard Model in the heavy $t$-quark mass limit $m_{t} \gg m_{w}$. In the $\ms$-scheme the two-loop electroweak correction to the ${\cal…

High Energy Physics - Phenomenology · Physics 2009-12-30 A. I. Bochkarev , R. S. Willey

The talk summarises a calculation of the two-point functions for $\Delta S=1$ current-current and QCD-penguin operators, as well as for the $\Delta S=2$ operator, at the next-to-leading order. The size of the gluonic corrections to…

High Energy Physics - Phenomenology · Physics 2009-10-28 Matthias Jamin

We review how a specific resummation of the so-called "delta-expansion", applied to the QCD Lagrangian, transforms the ordinary perturbative expansion in $\alpha_s$ into an expansion in an arbitrary mass parameter, around the basic scale…

High Energy Physics - Phenomenology · Physics 2009-10-30 J. -L. Kneur

Calculations of radiative corrections to the top quark width are reviewed. QCD effects are discussed for $t-\bar t$ systems produced in $e^+e^-$ annihilation near the energy threshold.}

High Energy Physics - Phenomenology · Physics 2007-05-23 Marek Jeżabek , Johann H. Kühn , Thomas Teubner

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

We show how radiative QCD corrections calculated in terms of quarks can be incorporated at the hadron level in inclusive semileptonic B-meson decays. The bound state effects are described by a momentum distribution function of the $b$…

High Energy Physics - Phenomenology · Physics 2011-09-13 Changhao Jin , Emmanuel A. Paschos

When the QCD axion is absent in full theory, the strong $CP$ problem has to be explained by an additional mechanism, e.g., the left-right symmetry. Even though tree-level QCD $\bar\theta$ parameter is restricted by the mechanism, radiative…

High Energy Physics - Phenomenology · Physics 2025-09-22 Junji Hisano , Teppei Kitahara , Naohiro Osamura , Atsuyuki Yamada

We present a simple method for considering radiative corrections. Precision data are well described by an adequate Born approximation and only the first evidence for deviations from the tree level formulas and the presence of the loop…

High Energy Physics - Phenomenology · Physics 2007-05-23 M. Vysotsky , ITEP , Moscow , Russia

In supersymmetric theories, the top quark can decay into its scalar partner plus a neutralino, with an appreciable rate. We calculate the $O(\alpha_s)$ QCD corrections to this decay mode in the minimal supersymmetric extension of the…

High Energy Physics - Phenomenology · Physics 2009-10-28 A. Djouadi , W. Hollik , C. Junger

An outline is given of an extended perturbative solution of Euclidean QCD which systematically accounts for a class of nonperturbative effects, while allowing renormalization by the perturbative counterterms. Proper vertices Gamma are…

High Energy Physics - Theory · Physics 2014-11-18 M. Stingl