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Related papers: Light fermion masses and chiral freedom

200 papers

We investigate topology in lattice simulations of QCD with two flavours of dynamical Wilson fermions. At various sea quark masses we find reasonable agreement between results for the topological charge from fermionic and gluonic…

High Energy Physics - Lattice · Physics 2008-11-26 Gunnar S. Bali , Norbert Eicker , Thomas Lippert , Hartmut Neff , Boris Orth , Klaus Schilling , Thorsten Struckmann , Jochen Viehoff

We present results from a simulation of quenched overlap fermions with L\"uscher-Weisz gauge field action on lattices up to $24^3 48$ and for pion masses down to $\approx 250$ MeV. Among the quantities we study are the pion, rho and nucleon…

High Energy Physics - Lattice · Physics 2008-11-26 D. Galletly , M. Gürtler , R. Horsley , H. Perlt , P. E. L. Rakow , G. Schierholz , A. Schiller , T. Streuer

The quark-lepton mass problem and the ideas of mass protection are reviewed. The Multiple Point Principle is introduced and used within the Standard Model to predict the top quark and Higgs particle masses. We discuss the lightest family…

High Energy Physics - Phenomenology · Physics 2007-05-23 C. D. Froggatt

We present results for the light, strange and charm quark masses using $N_f=2+1+1$ twisted mass fermion ensembles at three values of the lattice spacing, including two ensembles simulated with the physical value of the pion mass. The…

A parameter free, model independent analysis of quark mass matrices is carried out. We find a representation in terms of a diagonal mass matrix for the down (up) quarks and a suitable matrix for the up (down) quarks, such that the mass…

High Energy Physics - Phenomenology · Physics 2011-02-01 D. Falcone , O. Pisanti , L. Rosa

We present simulation results for lattice QCD with chiral fermions in small volumes, where the epsilon-expansion of chiral perturbation theory applies. Our data for the low lying Dirac eigenvalues, as well as mesonic correlation functions,…

High Energy Physics - Lattice · Physics 2009-11-11 W. Bietenholz , T. Chiarappa , K. Jansen , K. -I. Nagai , S. Shcheredin

We present an updated analysis of the quark mass dependence of the nucleon mass and nucleon axial-vector coupling g_A, comparing different formulations of SU(2) Baryon Chiral Effective Field Theory, with and without explicit delta (1232)…

High Energy Physics - Lattice · Physics 2009-11-11 M. Procura , B. U. Musch , T. R. Hemmert , W. Weise

Soft-pion theorems are used to show how chiral symmetry constrains the contributions of low-momentum pions to the quark condensate, the pion decay constant and hadron masses, all of which have been proposed as signals of partial restoration…

Nuclear Theory · Physics 2007-05-23 Michael C. Birse

We construct a Left-Right symmetric model in which the number of generation is related to Grassmann variables. We introduce two sets of complex Grassmann variables ($\theta^1_q$,$\theta^2_q$), ($\theta^1_l$, $\theta ^2_l$) and associate…

High Energy Physics - Phenomenology · Physics 2009-10-22 Xiao-Gang He

The effect of cooling on a number of observables is calculated in SU(2) lattice gauge theory. The static quark-antiquark potential and spin-dependent interactions are studied, and the topological charge is monitored. The chiral symmetry…

High Energy Physics - Lattice · Physics 2010-11-01 Howard D. Trottier , R. M. Woloshyn

A model is constructed for a chiral abelian gauge-interaction of fermions and a potential of three higgses, so that the potential possesses a discrete symmetry of the vacuum state, which provides the introduction of three generations for…

High Energy Physics - Phenomenology · Physics 2007-05-23 V. V. Kiselev

We present results on the light hadron spectrum and quark mass in two-flavor QCD calculated with small sea quark masses down to $m_{PS}/m_{V}=0.35$. The configurations are generated using the RG improved gauge and tadpole-improved clover…

Several phenomenological features of fermion masses and mixings can be accounted for by a simple model for fermion mass matrices, which suggests an underlying U(2) horizontal symmetry. In this context, it is also proposed how an approximate…

High Energy Physics - Phenomenology · Physics 2009-11-07 D. Falcone

We calculate the quark mass dependence of both isovector and isoscalar anomalous magnetic moments of the nucleon in a chiral effective field theory with explicit pion, nucleon and Delta(1232) degrees of freedom to leading-one-loop order. In…

High Energy Physics - Lattice · Physics 2007-05-23 Thomas R. Hemmert , Wolfram Weise

Inspired by the small mass-squared difference measured in the solar neutrino oscillation experiments and by the testability, we suggest that a limit of the partial mass degeneracy, in which masses of the first two generation fermions are…

High Energy Physics - Phenomenology · Physics 2014-05-07 Takeshi Araki , Hiroyuki Ishida

We study dynamical mass generation in QED in (2+1) dimensions using Hamiltonian lattice methods. We use staggered fermions, and perform simulations with explicit dynamical fermions in the chiral limit. We demonstrate that a recently…

High Energy Physics - Lattice · Physics 2009-11-07 Pieter Maris , Dean Lee

Heavy baryon chiral perturbation theory for pentaquarks is applied beyond leading order. The mass splitting in the pentaquark anti-decuplet is calculated up to NNLO. An expansion in the coupling of pentaquarks to non-exotic baryons…

High Energy Physics - Phenomenology · Physics 2009-11-10 Vivek Mohta

We discuss three possible ways to address quantum physics behind chiral magnetic effect and electric charge fluctuation patterns in heavy ion collisions. The first one makes use of P-parity violation probed by local order parameters, the…

High Energy Physics - Phenomenology · Physics 2010-12-23 V. Orlovsky , V. Shevchenko

The environment generated in the mid-rapidity region of a high-energy nuclear collision endows the pionic degrees of freedom with a time-dependent effective mass. Its specific evolution provides a mechanism for the production of…

Nuclear Theory · Physics 2014-11-18 Jorgen Randrup

The quark-connected part of the hadronic light-by-light scattering contribution to the muon's anomalous magnetic moment is computed using lattice QCD with chiral fermions. We report several significant algorithmic improvements and…

High Energy Physics - Lattice · Physics 2016-01-20 Thomas Blum , Norman Christ , Masashi Hayakawa , Taku Izubuchi , Luchang Jin , Christoph Lehner
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