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Related papers: The b -> s gamma decay revisited

200 papers

We investigate the influence of the R-parity violating couplings lambda, lambda' and lambda'' on the branching ratio of b to s gamma in leading logarithmic approximation. The operator basis is enlarged and the corresponding gamma-matrix…

High Energy Physics - Phenomenology · Physics 2009-10-31 Thomas Besmer , Andreas Steffen

We present a determination of a new class of Feynman diagrams relevant for second-order QCD corrections to the top quark decay t -> b W. Modern computing techniques allow us to perform a reduction of the original loop integrals to master…

High Energy Physics - Phenomenology · Physics 2017-08-23 Maciej Slusarczyk

The decay of B mesons can be predicted within the Heavy Quark Expansion as the decay of a free bottom quark plus corrections which are suppressed by powers of $1/m_b$. This contribution to Loops&Legs 2024 describes the calculation of the…

High Energy Physics - Phenomenology · Physics 2024-07-02 Manuel Egner

We report the results of a new calculation of soft-gluon corrections in B -> X_s l^+ l^- decays. In particular, we present the first calculation of bremsstrahlung and corresponding virtual terms to the lepton forward-backward asymmetry,…

High Energy Physics - Phenomenology · Physics 2009-11-07 A. Ghinculov , T. Hurth , G. Isidori , Y. -P. Yao

We calculate the two-loop $10 \times 10$ anomalous dimension matrix ${\cal O}(\alpha_s^{2})$ involving current-current operators, QCD penguin operators, and electroweak penguin operators especially relevant for $\Delta S=1$ weak…

High Energy Physics - Phenomenology · Physics 2009-10-22 Andrzej J. Buras , Matthias Jamin , Markus E. Lautenbacher , Peter H. Weisz

We derive a class of formulae relating moments of B -> Xu l nu to B -> Xs gamma in the shape function region, where m_X^2 ~ m_b Lambda_QCD. We also derive an analogous class of formulae involving the decay B -> Xs l+ l-. These results…

High Energy Physics - Phenomenology · Physics 2008-12-16 Keith S. M. Lee

We prove optimal decay estimates for positive solutions to elliptic p-Laplacian problems in the entire Euclidean space, when a critical nonlinearity with a decaying source term is considered. Also gradient decay estimates are furnished. Our…

Analysis of PDEs · Mathematics 2025-02-28 Laura Baldelli , Umberto Guarnotta

We extend the threshold resummation of the large logarithms $\ln x$ which appear in factorization formulas for exclusive $B$ meson decays, $x$ being a spectator momentum fraction, to the next-to-leading-logarithm (NLL) accuracy. It is shown…

High Energy Physics - Phenomenology · Physics 2021-07-28 Zhi-Qing Zhang , Hsiang-nan Li

We compute the two-loop BSM contributions to the $h\longrightarrow \gamma\gamma$ decay width in the aligned THDM. We adopt the simplifying assumptions of vanishing EW gauge couplings and vanishing mass of the SM-like Higgs boson, which…

High Energy Physics - Phenomenology · Physics 2023-10-13 Giuseppe Degrassi , Pietro Slavich

We propose a treatment of $\gamma^5$ in dimensional regularization which is based on an algebraically consistent extension of the Breitenlohner-Maison-'t Hooft-Veltman (BMHV) scheme; we define the corresponding minimal renormalization…

High Energy Physics - Theory · Physics 2009-10-31 M. Pernici

We consider the Banfi-Marchesini-Smye (BMS) equation which resums non-global energy logarithms in the QCD evolution of the energy lost by a pair of jets via soft radiation at large angles. We identify a new physical regime where, besides…

High Energy Physics - Phenomenology · Physics 2018-04-04 Y. Hatta , E. Iancu , A. H. Mueller , D. N. Triantafyllopoulos

We propose a gamma5 scheme in dimensional regularization by analytically continuing the dimension after all the gamma5 matrices have been moved to the rightmost position. All Feynman amplitudes corresponding to diagrams with no fermion…

High Energy Physics - Theory · Physics 2009-05-12 Er-Cheng Tsai

We compute the effective hamiltonian for non-leptonic |Delta F| = 1 decays in the standard model including next-to-next-to-leading order QCD corrections. In particular, we present the complete three-loop anomalous dimension matrix…

High Energy Physics - Phenomenology · Physics 2009-09-10 Martin Gorbahn , Ulrich Haisch

We compute the complete O(alphas^2) anomalous dimension matrix relevant for the b to s gamma, b to s gluon and b to s l+l- transitions in the standard model and some of its extensions. For radiative decays we confirm the results of Misiak…

High Energy Physics - Phenomenology · Physics 2008-11-26 Paolo Gambino , Martin Gorbahn , Ulrich Haisch

We propose the use of B -->D^**K decay modes for a theoretically clean determination of the weak phase gamma. The self tagging decays of the neutral D^** mesons, makes a measurement of the b --> u\bar{c}s amplitude feasible. This overcomes…

High Energy Physics - Phenomenology · Physics 2009-11-10 Nita Sinha

The goal of the SIMBA collaboration is to provide a global fit to the available measurements of inclusive B -> X_s gamma and B -> X_u l nu decays. By performing a global fit one is able to simultaneously determine the relevant…

High Energy Physics - Phenomenology · Physics 2013-03-06 Florian U. Bernlochner , Heiko Lacker , Zoltan Ligeti , Iain W. Stewart , Frank J. Tackmann , Kerstin Tackmann

In our previous paper we applied U-spin symmetry to charmless hadronic B+- --> M0 M+- decays for the purpose of precise extraction of the unitarity angle gamma. In this paper we extend our approach to neutral B0 and Bs --> M1 M2 decays. A…

High Energy Physics - Phenomenology · Physics 2008-11-26 Amarjit Soni , Denis A. Suprun

We compute the complete two-loop O(alpha) Wilson coefficients relevant for radiative decays of the B meson in the SM. This is a necessary step in the calculation of the O(alpha alpha_s^n ln^n m_b/M_W) corrections and improves on our…

High Energy Physics - Phenomenology · Physics 2009-11-07 Paolo Gambino , Ulrich Haisch

Corrections to the superallowed beta decay matrix elements are evaluated in perturbation theory using the notion of the isovector monopole resonance. The calculation avoids the separation into different contributions and thus presents a…

Nuclear Theory · Physics 2009-11-13 N. Auerbach

Recently, it was proposed to use measurements of Bd(t) -> D(*)+ D(*)- and Bd -> Ds(*)+ D(*)- decays to measure the CP phase gamma. In this paper, we present the extraction of gamma using this method. We find that gamma is favored to lie in…

High Energy Physics - Phenomenology · Physics 2010-11-23 Justin Albert , Alakabha Datta , David London