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Related papers: Quark mass effects to \sigma(e^+e^- -> hadrons) at…

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We explore a framework for the computation of quark mass ratios and CKM mixing angles based on an SU(3) family gauge symmetry. The four ratios md/mb, ms/mb, mu/mt, and mc/mt can be fit at one-loop in the family gauge interaction. The same…

High Energy Physics - Phenomenology · Physics 2009-11-11 Thomas Appelquist , Yang Bai , Maurizio Piai

Pole masses of quarks in the quantum chromodynamics are calculated to the two-loop order in the framework of the regularization by dimensional reduction. For the diagram with a light quark loop, the non-Euclidean asymptotic expansion is…

High Energy Physics - Phenomenology · Physics 2009-10-30 L. V. Avdeev , M. Yu. Kalmykov

We derive general relations among hadronic form factors involving one heavy meson $b\bar{q}$ and another, not necessarily heavy, meson $Q\bar{q}$. The relations are valid to all orders of mass corrections of $m_Q$ .

High Energy Physics - Phenomenology · Physics 2007-05-23 Patrick J. O'Donnell , Humphrey K. K. Tung

It is hoped that the accuracy of a variety of lattice calculations will be improved by perturbatively eliminating effects proportional to the lattice spacing. In this paper, we apply this improvement program to the heavy quark effective…

High Energy Physics - Phenomenology · Physics 2010-11-01 Oscar F. Hernandez , Brian R. Hill

The electromagnetic excitation of the nucleon resonances is studied in the framework of Constituent Quark Models. Particular attention is devoted to the transition to the $\Delta$ resonance and to the issue of a possible deformation of…

Nuclear Theory · Physics 2015-06-22 M. M. Giannini

The QCD one-loop renormalization is restudied in a mass-dependent subtraction scheme in which the quark mass is not set to vanish and the renormalization point is chosen to be an arbitrary timelike momentum. The correctness of the…

High Energy Physics - Theory · Physics 2007-05-23 Jun-Chen Su , Lian-You Shan , Ying-Hui Cao

The decay $\eta \to 3 \pi$ proceeds exclusively through isospin violating operators and is therefore an excellent probe to examine the strength of isospin breaking in the strong interaction. The latter can be expressed through the quark…

High Energy Physics - Phenomenology · Physics 2018-09-27 Stefan Lanz

The key quantity of the heavy quark theory is the quark mass $m_Q$. Since quarks are unobservable one can suggest different definitions of $m_Q$. One of the most popular choices is the pole quark mass routinely used in perturbative…

High Energy Physics - Phenomenology · Physics 2010-11-01 I. I. Bigi , M. A. Shifman , N. G. Uraltsev , A. I. Vainshtein

Quantum chromodynamics (QCD) effects in the semileptonic decay b -> c l nu are evaluated to the second order in the coupling constant, O(alpha_s^2), and to several orders in the expansion in quark masses, m_c/m_b. Corrections are calculated…

High Energy Physics - Phenomenology · Physics 2008-11-26 Alexey Pak , Andrzej Czarnecki

We show that maximally twisted mass fermions can be employed to regularize on the lattice the fully unquenched QCD+QED theory with vanishing $\theta$-term. We discuss how the critical mass of the up and down quarks can be conveniently…

High Energy Physics - Lattice · Physics 2016-12-08 Roberto Frezzotti , Giancarlo Rossi , Nazario Tantalo

We present a calculation of the up, down, strange and charm quark masses performed within the lattice QCD framework. We use the twisted mass fermion action and carry out simulations that include in the sea two light mass-degenerate quarks,…

Quarkonium resonances in the complex-mass scale are studied. Relativistic quark potential model is used to describe the quark-antiquark system. The complex-mass formula is obtained from two exact asymptotic solutions for the QCD motivated…

High Energy Physics - Phenomenology · Physics 2015-11-25 M. N. Sergeenko

Perturbative series of some quantities in quantum field theories, such as the pole mass of a quark, suffer from a kind of divergence called renormalon divergence. In this paper, the leading renormalon in the pole mass is investigated, and a…

High Energy Physics - Phenomenology · Physics 2017-10-03 Javad Komijani

We compute the relation between the quark mass defined in the minimal modified $\MSbar$ scheme and the mass defined in the ``Regularization Invariant" scheme (RI), up to the NNLO order. The RI scheme is conveniently adopted in lattice QCD…

High Energy Physics - Phenomenology · Physics 2009-10-31 E. Franco , V. Lubicz

Renormalization factors for local vector and axial vector currents for the Wilson quark action are perturbatively calculated to one loop order including finite quark masses from the ratio of the on-shell quark matrix elements in the Feynman…

High Energy Physics - Lattice · Physics 2009-10-30 Yoshinobu Kuramashi

The dependence of the pseudoscalar meson masses and decay constants on sea and valence quark masses is compared to next-to-leading order (NLO) Chiral Perturbation Theory (ChPT). The numerical simulations with two light dynamical quark…

High Energy Physics - Lattice · Physics 2008-11-26 F. Farchioni , I. Montvay , E. Scholz , L. Scorzato

Hadron masses can be decomposed as a sum of components which are defined through hadronic matrix elements of QCD operators. The components consist of the quark mass term, the quark energy term, the glue energy term and the trace anomaly…

High Energy Physics - Lattice · Physics 2014-11-05 Yi-Bo Yang , Ying Chen , Terrence Draper , Ming Gong , Keh-Fei Liu , Zhaofeng Liu , Jian-Ping Ma

The form factors for the $K_{\ell 3}$ semileptonic decay are computed to order $O(p^4)$ in generalized chiral perturbation theory. The main difference with the standard $O(p^4)$ expressions consists in contributions quadratic in quark…

High Energy Physics - Phenomenology · Physics 2009-10-31 N. H. Fuchs , M. Knecht , J. Stern

Quark mass reweighting can be used to tune the mass of dynamical quarks. The basic idea is to use gauge field ensembles generated at some bare mass parameters to evaluate observables at different bare sea quark masses. This involves the…

High Energy Physics - Lattice · Physics 2015-01-28 Björn Leder , Jacob Finkenrath

We study the effect of the charm quark mass in the CTEQ global analysis of parton distribution functions (PDFs) of the proton. Constraints on the $\bar{\rm MS}$ mass of the charm quark are examined at the next-to-next-to-leading order…

High Energy Physics - Phenomenology · Physics 2015-06-15 Jun Gao , Marco Guzzi , Pavel M. Nadolsky