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Related papers: QCD in the delta-Regime

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We analyze the statistical properties of the spectrum of the QCD Dirac operator at low energy in a finite box of volume $L^4$ by means of partially quenched Chiral Perturbation Theory (pqChPT), a low-energy effective field theory based on…

High Energy Physics - Theory · Physics 2009-10-31 D. Toublan , J. J. M. Verbaarschot

We investigate the properties of the pion quasiparticle in the low-temperature phase of two-flavor QCD on the lattice with support from chiral effective theory. We find that the pion quasiparticle mass is significantly reduced compared to…

High Energy Physics - Lattice · Physics 2015-09-22 Bastian B. Brandt , Anthony Francis , Harvey B. Meyer , Daniel Robaina

We present results of a high-statistics study of scalar and pseudoscalar meson propagators in quenched QCD at two values of lattice spacing, beta = 5.7 and 5.9, with clover-improved Wilson fermions. The study of the chiral limit is…

High Energy Physics - Lattice · Physics 2009-11-07 W. Bardeen , E. Eichten , H. Thacker

We compute the chiral condensate in 2+1-flavor QCD through the spectrum of low-lying eigenmodes of Dirac operator. The number of eigenvalues of the Dirac operator is evaluated using a stochastic method with an eigenvalue filtering technique…

High Energy Physics - Lattice · Physics 2016-08-22 Guido Cossu , Hidenori Fukaya , Shoji Hashimoto , Takashi Kaneko , Jun-Ichi Noaki

Chiral low-energy constants incorporate short-distance information from the dynamics involving heavier degrees of freedom not present in the chiral Lagrangian. We have studied the contribution of the lightest resonances to the chiral…

High Energy Physics - Phenomenology · Physics 2008-11-26 J. Portoles

We study SU(3)$_L\timesSU(3)_R$ chiral quark model of mesons up to the next to leading order of $1/N_c$ expansion. Composite vector and axial-vector mesons resonances are introduced via non-linear realization of chiral SU(3) and vector…

High Energy Physics - Phenomenology · Physics 2007-05-23 Xiao-Jun Wang , Mu-Lin Yan

An updated and extended analysis of the quark mass dependence of the nucleon's axial vector coupling constant g_A is presented in comparison with state-of-the-art lattice QCD results. Special emphasis is placed on the role of the…

High Energy Physics - Lattice · Physics 2008-11-26 M. Procura , B. U. Musch , T. R. Hemmert , W. Weise

Based on the AdS/CFT correspondence we study the breaking of the chiral symmetry in QCD using a simple five dimensional model. The model gives definite predictions for the spectrum of vector mesons, their decay constants and interactions as…

High Energy Physics - Phenomenology · Physics 2008-11-26 Leandro Da Rold , Alex Pomarol

We analyze (using a chiral effective Lagrangian model) the scalar and pseudoscalar meson mass spectrum of QCD at finite temperature, above the chiral transition at $T_c$, looking, in particular, for signatures of a possible breaking of the…

High Energy Physics - Phenomenology · Physics 2014-10-15 Enrico Meggiolaro

We study the low energy dynamics of pions in a gravity dual of chiral symmetry breaking. The string theory construction consists of a probe D7 brane in the Constable Myers non-supersymmetric background, which has been shown to describe…

High Energy Physics - Theory · Physics 2009-11-10 Nick Evans , Jonathan P. Shock

The spectral density of euclidean Dirac operator is investigated in partially quenched QCD with arbitrary quark masses. A representation of scalar and pseudoscalar correlators in terms of the spectral density is discussed. The spectral…

High Energy Physics - Phenomenology · Physics 2009-10-31 K. Zyablyuk

In the past year domain wall fermion simulations have moved from exploratory stages to the point where systematic effects can be studied with different gauge couplings, volumes, and lengths in the fifth dimension. Results are presented here…

High Energy Physics - Lattice · Physics 2009-10-31 Matthew Wingate

Recent conceptual, algorithmic and technical advances allow numerical simulations of lattice QCD with Wilson quarks to be performed at significantly smaller quark masses than was possible before. Here we report on simulations of two-flavour…

High Energy Physics - Lattice · Physics 2010-02-03 L. Del Debbio , L. Giusti , M. Lüscher , R. Petronzio , N. Tantalo

We study the quark-mass dependence of $\omega\to3\pi$ decays, based on a dispersion-theoretical framework. We rely on the quark-mass-dependent scattering phase shift for the pion-pion $P$-wave extracted from unitarized chiral perturbation…

High Energy Physics - Phenomenology · Physics 2018-10-31 Maximilian Dax , Tobias Isken , Bastian Kubis

The mass spectrum of Delta resonances is compared to predictions based on three quark-model variants, to predictions assuming that chiral symmetry is restored in high-mass baryon resonances, and to predictions derived from AdS/QCD. The…

High Energy Physics - Phenomenology · Physics 2009-09-29 E. Klempt

We study the volume dependence of the left-current correlator with non-degenerate quark masses to next-to-leading order in the chiral expansion. We consider three possible regimes: all quark masses are in the $\epsilon$-regime, all are in…

High Energy Physics - Lattice · Physics 2010-02-03 F. Bernardoni , P. Hernández

We study supersymmetric QCD with N_f<N_c in the limit of small supersymmetry-breaking masses and smaller quark masses using the weak-coupling Kahler potential. We calculate the full spectrum of this theory, which manifests a chiral symmetry…

High Energy Physics - Theory · Physics 2016-08-25 Stephen P. Martin , James D. Wells

We present results for meson masses and decay constants measured on 24^3x64 lattices using the domain wall fermion formulation with an extension of the fifth dimension of L_s=16 for N_f=2+1 dynamical quark flavors. The lightest dynamical…

High Energy Physics - Lattice · Physics 2012-08-27 UKQCD Collaboration , M. F. Lin , E. E. Scholz

We study the quark mass expansion of the axial-vector coupling constant g_A of the nucleon. The aim is to explore the feasibility of chiral effective field theory methods for extrapolation of lattice QCD results - so far determined at…

High Energy Physics - Lattice · Physics 2008-11-26 Thomas R. Hemmert , Massimiliano Procura , Wolfram Weise

We perform a detailed, fully-correlated study of the chiral behavior of the pion mass and decay constant, based on 2+1 flavor lattice QCD simulations. These calculations are implemented using tree-level, O(a)-improved Wilson fermions, at…