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Related papers: Radiative Corrections to K_l2 decays

200 papers

A reduced-order model algorithm, based on approximations of Lax pairs, is proposed to solve nonlinear evolution partial differential equations. Contrary to other reduced-order methods, like Proper Orthogonal Decomposition, the space where…

Numerical Analysis · Mathematics 2012-11-20 Jean-Frédéric Gerbeau , Damiano Lombardi

The paper deals with a next-to-leading order analysis of the radiative $B \to K^* \gamma$ decay. Working in a PQCD approach, we compute the correction to the essential form factor, coming from a single gluon exchange with the spectator. We…

High Energy Physics - Phenomenology · Physics 2007-10-23 Ciprian Dariescu , Marina-Aura Dariescu

In many calculations of the two--photon decay of hadronic molecules, the decay matrix element is estimated using the wave function at the origin prescription, in analogy to the two-photon decay of parapositronium. We question the…

High Energy Physics - Phenomenology · Physics 2008-11-26 C. Hanhart , Yu. S. Kalashnikova , A. E. Kudryavtsev , A. V. Nefediev

We review the status of theory and experiment of very rare and forbidden kaon decays. We then review the radiative non-leptonic decays, and the associated Dalitz pair modes. We pay particular attention to the study of long distance physics…

High Energy Physics - Phenomenology · Physics 2009-10-22 L. Littenberg , G. Valencia

The decays $K \to \pi l^{+} l^{-}$, $K \to \pi \gamma \gamma $ and $K \to \pi \nu {\bar \nu}$ are investigated using the higher order terms of the chiral perturbation theory. The counterterms induced by strong, weak and electromagnetic…

High Energy Physics - Phenomenology · Physics 2007-05-23 S. Fajfer

We discuss the uses of conversion electron pairs for extracting photon polarization information in weak radiative B decays. Both cases of leptons produced through a virtual and real photon are considered. Measurements of the angular…

High Energy Physics - Phenomenology · Physics 2009-10-31 Yuval Grossman , Dan Pirjol

Corrections of order $\alpha_s^4$ for the axial singlet contributions for the decay rates of the $Z$-boson into hadrons are evaluated in the limit of the heavy top quark mass. Combined with recently finished ${\cal O}(\alpha_s^4)$…

High Energy Physics - Phenomenology · Physics 2015-06-03 P. A. Baikov , K. G. Chetyrkin , J. H. Kühn , J. Rittinger

The largest contribution to the CP violating K_L-K_S mixing parameter \epsilon_K comes from second order weak interactions at short distances and can be accurately determined by a combination of electroweak perturbation theory and the…

High Energy Physics - Lattice · Physics 2012-01-11 Norman H. Christ

We analyse $B\to K^\ast \ell\ell$ decays in the region of low hadronic recoil, where an operator product expansion (OPE) in $1/m_b$ applies. Using a local model for charm contributions based on $e^+ e^- \to hadrons$ against the OPE provides…

High Energy Physics - Phenomenology · Physics 2017-02-01 Simon Braß , Gudrun Hiller , Ivan Nisandzic

We present a theoretical framework within which both the real and imaginary parts of the complex, two-photon exchange amplitude contributing to $K_L\rightarrow\mu^+\mu^-$ decay can be calculated using lattice QCD. The real part of this…

High Energy Physics - Phenomenology · Physics 2024-06-12 En-Hung Chao , Norman Christ

We compute the decay rate of the Standard Model Higgs boson to bottom quarks to order $\alpha\alpha_s$. We apply the optical theorem and calculate the imaginary part of three-loop corrections to the Higgs boson propagator using asymptotic…

High Energy Physics - Phenomenology · Physics 2015-11-11 Luminita Mihaila , Barbara Schmidt , Matthias Steinhauser

We report on some recent progress made in understanding weak matrix elements of mesons in the context of the next-to-leading order of the large-Nc approximation to QCD. Specifically, we first use the example of the weak contributions to the…

High Energy Physics - Phenomenology · Physics 2008-11-26 M. Knecht , S. Peris , E. de Rafael , .

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

We calculate the $\alpha_s$ corrections to the form factors which parameterize the hadronic tensor relevant for inclusive semileptonic $B \rightarrow X \tau\bar\nu_{\tau}$ and $\Lambda_b \rightarrow X \tau\bar\nu_{\tau}$ decays. We apply…

High Energy Physics - Phenomenology · Physics 2008-02-03 C. G. Boyd , Z. Guralnik , M. Schmaltz , F. J. Vegas

Theoretical predictions for the branching ratios of the $B \rightarrow X_s\,\gamma$ and $B \rightarrow K^*\,\gamma$ decays are calculated in the Standard Model and in the (type II) two-Higgs-doublet model. Both the complete leading and the…

High Energy Physics - Phenomenology · Physics 2009-09-25 M. Ciuchini

We show that long distance contributions to the rare decays K -> pi nu nu-bar and K -> pi l+ l- can be computed using lattice QCD. The proposed approach requires well established methods, successfully applied in the calculations of…

High Energy Physics - Lattice · Physics 2009-11-11 Gino Isidori , Guido Martinelli , Paolo Turchetti

A comprehensive overview of kaon decays is presented. The Standard Model predictions are discussed in detail, covering both the underlying short-distance electroweak dynamics and the important interplay of QCD at long distances. Chiral…

High Energy Physics - Phenomenology · Physics 2015-05-30 V. Cirigliano , G. Ecker , H. Neufeld , A. Pich , J. Portoles

In the framework of the nonrelativistic quantum chromodynamics factorization formalism, we study the processes of $\psi(nS)$ and $\Upsilon(nS)$ decay into a lepton pair or a charm pair associated with two jets up to the next-to-leading…

High Energy Physics - Phenomenology · Physics 2015-03-19 Hai-Ting Chen , Yu-Qi Chen , Wen-Long Sang

The interplay between short- and long-distance contributions to the K_L-->mu+ mu- decay amplitude is analyzed. The long-distance piece is estimated using chiral perturbation theory techniques and large-N_C considerations, leading to a…

High Energy Physics - Phenomenology · Physics 2009-10-31 D. Gomez Dumm , A. Pich

We consider the decay of an intermediate mass Higgs boson into hadrons up to order O(\alpha_s^3). The results from the diagrams containing only light degrees of freedom were recently computed in a previous work by K.G. Ch. (Phys. Lett. B…

High Energy Physics - Phenomenology · Physics 2011-01-13 K. G. Chetyrkin , M. Steinhauser