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Related papers: Mesons upon low-lying Dirac mode exclusion

200 papers

We study light scalar mesons with particular focus on the a_0(980) using lattice QCD with 2+1+1 dynamical quark flavors. To investigate the structure of these scalar mesons and to identify, whether a sizeable tetraquark component is…

We reconsider constraints on the eigenvalue density of the Dirac operator in the chiral symmetric phase of 2 flavor QCD at finite temperature. To avoid possible ultra-violet(UV) divergences, we work on a lattice, employing the overlap Dirac…

High Energy Physics - Lattice · Physics 2013-05-30 Sinya Aoki , Hidenori Fukaya , Yusuke Taniguchi

Euclidean space hadronic correlators are computed in quenched QCD at small quark mass using truncations of quark propagators which include or exclude low eigenvalue eigenmodes of the Dirac operator. High modes provide the dominant…

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

We study the a_0 and K_0^* light scalar mesons in 2+1 flavor full QCD. Particular attention is paid to fitting excited states, with an eye toward determining whether scattering states are revealed. An ultimate goal will be to see how…

High Energy Physics - Lattice · Physics 2010-01-21 Terrence Draper , Takumi Doi , Keh-Fei Liu , Devdatta Mankame , Nilmani Mathur , Xiangfei Meng

We study the properties of low-lying Dirac modes in quenched compact QED at $\beta =1.01$, employing $12^3\times N_t$ ($N_t =4,6,8,10,12$) lattices and the overlap formalism for the fermion action. We pay attention to the spatial…

High Energy Physics - Lattice · Physics 2008-11-26 Toru T. Takahashi

Recent studies on lattice QCD have shown the emergence of large symmetries at high temperature. This includes not only the restoration $SU(n_F)_L \times SU(n_F)_R$, but also the effective emergence of an unexpected symmetry group, namely…

High Energy Physics - Lattice · Physics 2021-07-02 Marco Catillo

We develop a generalization of low-mode averaging in which the number of low quark modes of the Dirac operator required for a constant variance reduction can be kept independent of the volume by exploiting their local coherence. Typically…

High Energy Physics - Lattice · Physics 2024-12-10 Roman Gruber , Tim Harris , Marina Krstic Marinkovic

We study the properties of low-lying Dirac modes in quenched compact QED at $\beta$=0.99, 1.01 and 1.03, employing $12^3\times 12$ lattices and the overlap formalism for the fermion action. We pay special attention to the spatial…

High Energy Physics - Lattice · Physics 2008-11-26 Toru T. Takahashi

We consider properties of zero and near-zero modes for overlap fermion operator in SU(2) lattice gluodynamics. The density of the states is of the order of Lambda(QCD) while the localization volume of the modes tends to zero in physical…

High Energy Physics - Lattice · Physics 2007-05-23 M. I. Polikarpov , F. V. Gubarev , S. M. Morozov , V. I. Zakharov

We study physics at temperatures just above the QCD phase transition (Tc) using chiral (overlap) Fermions in the quenched approximation of lattice QCD. Exact zero modes of the overlap Dirac operator are localized and their frequency of…

High Energy Physics - Lattice · Physics 2011-07-19 Rajiv V. Gavai , Sourendu Gupta , R. Lacaze

Remarkable symmetry properties appear to arise in lattice calculations of correlation functions in which the lowest-lying eigenmodes of the Dirac operator in quark propagators are removed by hand. The Banks-Casher relation ties the chiral…

High Energy Physics - Lattice · Physics 2016-03-02 Thomas D. Cohen

With increasing requirements for greater precision, it becomes essential to describe the effects of isospin breaking induced by both quark masses and electro-magnetic effects. In this work we perform a lattice analysis of the weak decay…

High Energy Physics - Lattice · Physics 2023-09-18 Z. R. Kordov , R. Horsley , W. Kamleh , Y. Nakamura , H. Perlt , P. E. L. Rakow , G. Schierholz , H. Stüben , R. D. Young , J. M. Zanotti

In this project we study the effect of the $U_A(1)$ anomaly for (2+1)-flavour QCD at high temperature. We apply the overlap operator as a tool to probe the topological properties of gauge field configurations which have been generated…

High Energy Physics - Lattice · Physics 2013-11-18 Sayantan Sharma , Viktor Dick , Frithjof Karsch , Edwin Laermann , Swagato Mukherjee

We describe and test a method known in the literature as low mode averaging to improve Euclidean two-point functions in lattice QCD using the low-lying eigenmodes of the Wilson-Dirac operator D. The contribution from the low modes is…

High Energy Physics - Lattice · Physics 2011-04-20 Gunnar Bali , Luca Castagnini , Sara Collins

We present the first study of treating b, c, and s quarks as Dirac fermions in lattice QCD with exact chiral symmetry. For 100 gauge configurations generated with single-plaquette action at beta = 7.2 on the 32^3 x 60 lattice, we compute…

High Energy Physics - Lattice · Physics 2008-11-26 Ting-Wai Chiu , Tung-Han Hsieh , Chao-Hsi Huang , Kenji Ogawa

We investigate the effects of low-lying fermion eigenmodes on the QCD partition function in the $\epsilon$-regime. The fermion determinant is approximated by a truncated product of low-lying eigenvalues of the overlap-Dirac operator. With…

High Energy Physics - Lattice · Physics 2009-11-11 Kenji Ogawa , Shoji Hashimoto

I propose a simple model of the distribution of the small eigenvalues of the QCD Dirac operator well above the finite temperature phase transition where chiral symmetry is restored and the spectral density at zero vanishes. Assuming the…

High Energy Physics - Lattice · Physics 2010-11-11 Tamas G. Kovacs

In the context of some deformed canonical commutation relations leading to isotropic nonzero minimal uncertainties in the position coordinates, a Dirac equation is exactly solved for the first time, namely that corresponding to the Dirac…

Mathematical Physics · Physics 2009-11-10 C. Quesne , V. M. Tkachuk

We evaluate the pseudoscalar-meson octet-baryon coupling constants and the corresponding axial charges in eight channels ($\pi N\N$, $\pi\Sigma\Sigma$, $\pi\Lambda\Sigma$, $K\Lambda N$, $K \Sigma N $, $\pi\Xi\Xi$, $K\Lambda\Xi$ and…

High Energy Physics - Lattice · Physics 2015-05-14 Toru T. Takahashi , Guray Erkol , Makoto Oka

Within the framework of the instantaneous Bethe-Salpeter equation, we present a detailed analysis of light meson spectra with respect to various parameterizations of confinement in Dirac space. Assuming a linearly rising quark-antiquark…

High Energy Physics - Phenomenology · Physics 2009-10-31 Ralf Ricken , Matthias Koll , Dirk Merten , Bernard Ch. Metsch , Herbert R. Petry