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Related papers: Quark mass effects in B -> Xs gamma

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We compute two-loop corrections to the vector current matching coefficient involving two heavy quark masses. The result is applied to the computation of the $\Upsilon(1S)$ decay width into an electron or muon pair. We complement the…

High Energy Physics - Phenomenology · Physics 2021-10-04 Manuel Egner , Matteo Fael , Jan Piclum , Kay Schoenwald , Matthias Steinhauser

The B -> X_s gamma branching ratio is currently measured with around 5% accuracy. Further improvement is expected from Belle II. To match such a precision on the theoretical side, evaluation of O(alpha_s^2) corrections to the partonic decay…

High Energy Physics - Phenomenology · Physics 2023-12-11 M. Czaja , M. Czakon , T. Huber , M. Misiak , M. Niggetiedt , A. Rehman , K. Schönwald , M. Steinhauser

Radiative QCD corrections significantly influence the theoretical predictions for the decay rates of the $Z$ and the Higgs boson. The status of the QCD calculations to the hadronic $Z$ width is reviewed. The role of mass corrections from…

High Energy Physics - Phenomenology · Physics 2007-05-23 K. G. Chetyrkin , J. H. Kühn , A. Kwiatkowski

We re-examine the lower bound on the mass of the Higgs boson, $M_H$, from Standard Model vacuum stability including next-to-leading-log radiative corrections. This amounts to work with the full one-loop effective potential, $V(\phi)$,…

High Energy Physics - Phenomenology · Physics 2009-10-28 J. A. Casas , J. R. Espinosa , M. Quiros

We present our results for three-loop anomalous dimensions necessary in analyzing $B{\to}X_s\gamma$ decay at the next-to-leading order in QCD. We combine them with other recently calculated contributions, obtaining a practically complete…

High Energy Physics - Phenomenology · Physics 2011-08-01 Konstantin Chetyrkin , Mikolaj Misiak , Manfred Munz

A detailed error analysis is carried out for the determination of the MSbar charm quark mass $\bar m_c(\bar m_c)$ from moments at order alpha_s^2 of the charm cross section in e^+e^- annihilation. To estimate the theoretical uncertainties…

High Energy Physics - Phenomenology · Physics 2008-11-26 A. H. Hoang , M. Jamin

The effect of non-zero c quark mass on b quark HQET Lagrangian, up to 1/m_b level, is calculated at two loops. The results are expressed in terms of dilogarithmic functions of m_c/m_b. This calculation involves on-shell two-loop…

High Energy Physics - Phenomenology · Physics 2011-01-25 A. I. Davydychev , A. G. Grozin

We determine the charm and bottom quark masses using the N$^3$LO perturbative expression of the ground state (pseudoscalar) energy of the bottomonium, charmonium and $B_c$ systems: the $\eta_b$, $\eta_c$ and $B_c$ masses. We work in the…

High Energy Physics - Phenomenology · Physics 2018-10-17 Clara Peset , Antonio Pineda , Jorge Segovia

The latest results of the ATLAS and CMS experiments indicate 116 GeV \lesssim M_H \lesssim 131 GeV and 115 GeV \lesssim M_H \lesssim 127 GeV, respectively, for the mass of the Higgs boson in the standard model (SM) at the 95% confidence…

High Energy Physics - Phenomenology · Physics 2015-06-03 Zhi-zhong Xing , He Zhang , Shun Zhou

QCD corrections to the electroweak one-loop result for the partial width $\Gamma(H\rightarrow b\bar{b})$ are studied. For the decay channel into bottom quarks the rate is affected by a virtual top quark through electroweak interactions. The…

High Energy Physics - Phenomenology · Physics 2009-10-28 A. Kwiatkowski , M. Steinhauser

The leading diagrammatic two-loop corrections are incorporated into the prediction for the mass of the lightest Higgs boson, $\mh$, in the Minimal Supersymmetric Standard Model (MSSM). The results, containing the complete diagrammatic…

High Energy Physics - Phenomenology · Physics 2009-10-31 S. Heinemeyer , W. Hollik , G. Weiglein

We study the uncertainties in the MSbar bottom quark mass determination using relativistic sum rules to O(alpha_S^2). We include charm mass effects and secondary b bbar production and treat the experimental continuum region more…

High Energy Physics - Phenomenology · Physics 2011-01-25 Gennaro Corcella , Andre H. Hoang

By combining the first unquenched lattice computation of the B-meson binding energy with the recently calculated two-loop contribution to the lattice HQET mass, we determine the $\bar{MS}$ b-quark mass, $\bar{m}_{b}(\bar{m}_{b})$ at the…

High Energy Physics - Lattice · Physics 2015-06-25 V. Gimenez , L. Giusti , F. Rapuano , G. Martinelli

We study the light and heavy quark mass dependence of the low-lying charmed mesons in the framework of one-loop HH$\chi$PT. The low energy constants are determined by analyzing the available lattice data from different LQCD simulations.…

High Energy Physics - Lattice · Physics 2025-06-13 F. Gil-Domínguez , R. Molina

Results are presented for the momentum dependent two-loop contributions of O(alpha_t alpha_s) to the masses and mixing effects in the Higgs sector of the MSSM. They are obtained in the Feynman-diagrammatic approach using a mixed…

High Energy Physics - Phenomenology · Physics 2014-09-25 S. Borowka , T. Hahn , S. Heinemeyer , G. Heinrich , W. Hollik

We consider the effects of a light quark mass in the soft-collinear effective theory (SCET) and we apply them to B -> X_s gamma in the endpoint region. We find that the reparameterization invariance can be extended by including the…

High Energy Physics - Phenomenology · Physics 2009-11-11 Junegone Chay , Chul Kim , Adam K. Leibovich

The experimental measurement of $B(b \to s\gamma)$ imposes important constraints on the charged Higgs boson mass in the MSSM. If squarks are in the few TeV range, the charged Higgs boson mass in the MSSM must satisfy $m_{H^{\pm}} \gsim 440$…

High Energy Physics - Phenomenology · Physics 2009-09-17 Marco A. Diaz , E. Torrente-Lujan , J. W. F. Valle

We perform a lattice study of heavy baryons, containing one ($\Lambda_b$) or two $b$-quarks ($\Xi_b$). Using the quenched approximation we obtain for the mass of $\Lambda_b$ $$ M_{\Lambda_b}= 5.728 \pm 0.144 \pm 0.018 {\rm GeV}.$$ The mass…

High Energy Physics - Lattice · Physics 2019-08-17 C. Alexandrou , A. Borrelli , S. Güsken , F. Jegerlehner , K. Schilling , G. Siegert , R. Sommer

The interpretation of the Higgs signal at \sim 126 GeV within the Minimal Supersymmetric Standard Model (MSSM) depends crucially on the predicted properties of the other Higgs states of the model, as the mass of the charged Higgs boson,…

High Energy Physics - Phenomenology · Physics 2013-09-25 M. Frank , L. Galeta , T. Hahn , S. Heinemeyer , W. Hollik , H. Rzehak , G. Weiglein

We compute the mass of the charm quark using both quenched and dynamical lattice QCD calculations. We examine the effects of mass dependent lattice artifacts by comparing two different formalisms for the heavy quarks. We take the continuum…

High Energy Physics - Lattice · Physics 2009-11-11 A. Dougall , C. M. Maynard , C. McNeile