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Related papers: Isospin symmetry breaking effects in the pion and …

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We present the first study of $N_f=2+1+1+1$ lattice QCD with domain-wall quarks. The $(b, c, s)$ quarks are physical, while the $(u, d)$ quarks are heavier than their physical masses, with the pion mass $ \sim 700 $ MeV. The gauge ensemble…

High Energy Physics - Lattice · Physics 2020-09-02 Ting-Wai Chiu

We review progress on hadron structure using lattice QCD simulations at or near to physical values of the QCD parameters. In particular, we discuss recent results on hadron masses, the nucleon charges, spin, gluon and quark unpolarized…

High Energy Physics - Lattice · Physics 2015-12-15 Constantia Alexandrou

Quantum fluctuations in QCD influence nucleon structure and interactions, with pion production serving as a key probe of chiral dynamics. In this study, we present a lattice QCD calculation of multipole amplitudes at threshold, related to…

High Energy Physics - Lattice · Physics 2025-04-23 Yu-Sheng Gao , Zhao-Long Zhang , Xu Feng , Lu-Chang Jin , Chuan Liu , Ulf-G. Meißner

We investigate the isospin symmetry breaking effects within a recently derived Nambu-Jona-Lasinio related model by fitting the measured pseudoscalar meson masses and weak decay couplings $f_\pi$, $f_K$. Our model contains the next to…

High Energy Physics - Phenomenology · Physics 2016-06-29 Alexander A. Osipov , Brigitte Hiller , Alex H. Blin

We present lattice-QCD results on the nucleon isovector axial, scalar and tensor charges, the isovector electromagnetic Dirac and Pauli form factors, and the connected parts of the isoscalar charges. The calculations have been done using…

High Energy Physics - Lattice · Physics 2014-05-14 Tanmoy Bhattacharya , Saul D. Cohen , Rajan Gupta , Anosh Joseph , Huey-Wen Lin , Boram Yoon

We investigate nucleon mass splitting at finite isospin chemical potential in the frame of two flavor Nambu--Jona-Lasinio model. It is analytically proved that, in the phase with explicit isospin symmetry breaking the proton mass decreases…

Nuclear Theory · Physics 2008-11-26 Sheng Chang , Jifeng Liu , Pengfei Zhuang

We determine the nucleon axial, scalar and tensor charges within lattice Quantum Chromodynamics including all contributions from valence and sea quarks. We analyze three gauge ensembles simulated within the twisted mass formulation at…

High Energy Physics - Lattice · Physics 2020-10-07 C. Alexandrou , S. Bacchio , M. Constantinou , K. Hadjiyiannakou , K. Jansen , G. Koutsou , A. Vaquero Aviles-Casco

I discuss recent progress made in calculating electromagnetic corrections in the framework of the effective field theory of QCD. In the case of elastic pion-pion scattering, strong interaction predictions have been worked out to two loop…

High Energy Physics - Phenomenology · Physics 2009-10-30 Ulf-G. Meißner

We investigate the utility of partially twisted boundary conditions in lattice calculations of meson observables. For dynamical simulations, we show that the pion dispersion relation is modified by volume effects. In the isospin limit, we…

High Energy Physics - Lattice · Physics 2008-11-26 F. -J. Jiang , B. C. Tiburzi

We present results on the mass of the nucleon and the $\Delta$ using two dynamical degenerate twisted mass quarks. The evaluation is performed at four quark masses corresponding to a pion mass in the range of 690-300 MeV on lattices of size…

We discuss the extraction of the electromagnetic and spin polarisabilities of nucleons from lattice QCD. We show that the external field method can be used to measure all the electromagnetic and spin polarisabilities including those of…

High Energy Physics - Lattice · Physics 2009-11-11 W. Detmold , B. C. Tiburzi , A. Walker-Loud

Isospin-breaking corrections pose a significant challenge to lattice simulations, both because of the splitting between the up and down quark masses and, in particular, the need to include QED effects. The RC* collaboration has developed…

In these proceedings we discuss recent progress in nucleon structure using lattice QCD simulations at or near the physical value of the pion mass. Main focus will be given in observables such as the nucleon axial charge and the first…

High Energy Physics - Lattice · Physics 2017-01-12 Martha Constantinou

We identify the global symmetries of SU(2) lattice gauge theory with N flavors of staggered fermion in the presence of a quark chemical potential mu, for fermions in both fundamental and adjoint representations, and anticipate likely…

High Energy Physics - Lattice · Physics 2009-01-07 S. Hands , I. Montvay , S. Morrison , M. Oevers , L. Scorzato , J. Skullerud

We determine the light baryon spectrum on ensembles generated by the Coordinated Lattice Simulations (CLS) effort, employing $N_f=2+1$ flavours of non-perturbatively improved Wilson fermions. The hadron masses are interpolated and…

We review the present status of the nucleon effective mass splitting $puzzle$ in asymmetric matter, with controversial predictions within both non-relativistic $and$ relativistic approaches to the effective in medium interactions. Based on…

Nuclear Theory · Physics 2015-06-26 M. Di Toro , M. Colonna , J. Rizzo

We present the QCD simulation of the first gauge ensemble of two degenerate light quarks, a strange and a charm quark with all quark masses tuned to their physical values within the twisted mass fermion formulation. Results for the…

We report on a lattice QCD calculation of the nucleon axial charge, $g_A$, using M\"{o}bius Domain-Wall fermions solved on the dynamical $N_f=2+1+1$ HISQ ensembles after they are smeared using the gradient-flow algorithm. The calculation is…

Mixing of the pseudoscalar mesons is discussed in the quark-flavor basis. The divergences of the axial vector currents which embody the axial vector anomaly, combined with the assumption that the decay constants follow the pattern of…

High Energy Physics - Phenomenology · Physics 2025-01-22 P. Kroll

Quantum chromodynamics (QCD) at non-zero isospin chemical potential is studied in a canonical approach by analyzing systems of fixed isospin number density. To construct these systems, we develop a range of new algorithms for performing the…

High Energy Physics - Lattice · Physics 2013-05-30 William Detmold , Kostas Orginos , Zhifeng Shi