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Related papers: Decoupling of charm beyond leading order

200 papers

We present analytical results for top-quark decay processes, in an effective field theory beyond the Standard Model, at next-to-leading order in QCD. We parametrize new physics effects using dimension-six operators, and consider all…

High Energy Physics - Phenomenology · Physics 2014-07-16 Cen Zhang

We provide a new determination of the charm quark mass using the Highly Improved Staggered Quark (HISQ) action, finding m_c(3 GeV) = 0.983(23) GeV. Our determination makes extensive use of second order lattice perturbation theory in…

High Energy Physics - Lattice · Physics 2019-08-13 I. F. Allison , K. Y. Wong , C. T. H. Davies , C. McNeile , H. D. Trottier , E. Dalgic , J. Wu , E. Follana , R. R. Horgan , G. P. Lepage , J. Shigemitsu

We study the dependence on the charm quark mass of the leading-order low-energy constants of the $\Delta S=1$ effective Hamiltonian, with the aim of elucidating the role of the charm mass scale in the $\Delta I=1/2$ rule for $K\to\pi\pi$…

High Energy Physics - Lattice · Physics 2016-07-08 Eric Endress , Carlos Pena

We review the most recent results from experiments studying systems containing charmed quarks. The selection reflects the presenter's bias, and there is an emphasis on decays of open charm. We discuss precision measurements of various…

High Energy Physics - Experiment · Physics 2007-05-23 Jim Napolitano

We report on recent progress on five-loop calculations in perturbative QCD. We discuss the computation of the perturbative quark condensate, decoupling in QCD, and the precision determination of charm and bottom quark masses. For the…

High Energy Physics - Phenomenology · Physics 2024-07-24 Andreas Maier , Peter Marquard , York Schröder

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

Effects of heavy sea quarks on the low energy physics are described by an effective theory where the expansion parameter is the inverse quark mass, 1/$M$. At leading order in 1/$M$ (and neglecting light quark masses) the dependence of any…

Charm spectroscopy has studied under a string model. Charmed baryons are composed of diquark and charm quark which are connected by a constant tension. In a diquark picture, the quantum numbers $J^P$ of confirmed baryons are well assigned.…

High Energy Physics - Phenomenology · Physics 2010-04-28 Q. W. Wang , P. M. Zhang

We review the aspects of chiral gauge theories related to the violation of the decoupling property. The case of the top quark is worked out in detail. The mechanism of anomaly cancellation in the low-energy effective theory is illustrated…

High Energy Physics - Phenomenology · Physics 2014-11-17 Ferruccio Feruglio

I outline the basic strategies for the computation of charm and bottom quark masses by means of lattice QCD, where particular emphasis is placed on the non-perturbative renormalization of the effective theory for the b-quark in heavy-light…

High Energy Physics - Lattice · Physics 2011-01-27 Jochen Heitger

Recent developments in charm physics within the standard model and beyond are reviewed. The precision study of leptonic charm meson decays accompanied with the constraints coming from K, B and tau physics enables to determine constraints on…

High Energy Physics - Phenomenology · Physics 2012-01-31 S. Fajfer

Heavy quark symmetry relations for $B\rightarrow De\bar \nu_e$ and $B\rightarrow D^*e \bar \nu_e$ form factors receive corrections suppressed by powers of the charm quark mass. For small up and down quark massed the leading corrections of…

High Energy Physics - Phenomenology · Physics 2009-10-22 Chi-Keung Chow , Mark B. Wise

In this work, the charm quark mass is obtained from a QCD sum rule analysis of the charmonium system. In our investigation we include results from nonrelativistic QCD at next-to-next-to-leading order. Using the pole mass scheme, we obtain a…

High Energy Physics - Phenomenology · Physics 2008-11-26 M. Eidemuller , M. Jamin

We determine the MS-bar charm quark mass from a charmonium QCD sum rules analysis. On the theoretical side we use input from perturbation theory at O(alpha_s^3). Improvements with respect to previous O(alpha_s^3) analyses include (1) an…

High Energy Physics - Phenomenology · Physics 2013-07-30 Bahman Dehnadi , Andre H. Hoang , Vicent Mateu , S. Mohammad Zebarjad

We present an update of results from the HPQCD collaboration on charm physics using the Highly Improved Staggered Quark action. This includes a precise determination of m_c using moments of current-current correlators combined with…

The meaning and the extraction of heavy quark masses are discussed. A simple production model is presented which incorporates the running of the heavy quark mass into perturbative calculations. The model offers the possibilities of (i)…

High Energy Physics - Phenomenology · Physics 2007-05-23 Thomas J. Weiler , K. Ghafoori--Tabrizi

We simulate a theory with two dynamical O($a$) improved Wilson quarks whose mass $M$ ranges from a factor eight up to a factor two below the charm quark mass and at three values of the lattice spacing ranging from 0.066 to 0.034 fm. This…

High Energy Physics - Lattice · Physics 2014-11-06 Francesco Knechtli , Andreas Athenodorou , Mattia Bruno , Jacob Finkenrath , Björn Leder , Marina Marinkovic , Rainer Sommer

By exploring heavy quark effective theory (HQET), we use theoretical available data for bottom mesons to analysis the masses and decays for n = 3 charm mesons. From the predicted masses, we studied ground state strong decay modes in terms…

High Energy Physics - Phenomenology · Physics 2022-05-04 Ritu Garg , Kundan Kumar , Alka Upadhyay

Charm asymmetries in fixed-target hadroproduction experiments are sensitive to power corrections to the QCD factorization theorem for heavy quark production. A power correction called heavy-quark recombination has recently been proposed to…

High Energy Physics - Phenomenology · Physics 2009-11-10 Thomas Mehen

In this talk I would like to discuss two aspects of charm physics. One is to show that many standard model predictions for rare decay modes (along with $D^0 -\bar{D}^0$ mixing and CP violation) are extremely small thus opening a window for…

High Energy Physics - Phenomenology · Physics 2011-04-15 Sandip Pakvasa