English
Related papers

Related papers: Systematic errors in extracting nucleon properties…

200 papers

We present results on the nucleon electromagnetic form factors within lattice QCD using two flavors of degenerate twisted mass fermions. Volume effects are examined using simulations at two volumes of spatial length L=2.1 fm and L=2.8 fm.…

High Energy Physics - Lattice · Physics 2015-03-18 C. Alexandrou , M. Brinet , J. Carbonell , M. Constantinou , P. A. Harraud , P. Guichon , K. Jansen , T. Korzec , M. Papinutto

The nucleon-pion-state contributions to QCD two-point and three-point functions relevant for lattice calculations of the nucleon electromagnetic form factors are studied in chiral perturbation theory. To leading order the results depend on…

High Energy Physics - Lattice · Physics 2021-10-01 Oliver Bar , Haris Colic

We present recent lattice results on the baryon spectrum, nucleon electromagnetic and axial form factors, nucleon to $\Delta$ transition form factors as well as the $\Delta$ electromagnetic form factors. The masses of the low lying baryons…

High Energy Physics - Lattice · Physics 2015-05-13 C. Alexandrou

We present results on the nucleon axial form factors within lattice QCD using two flavors of degenerate twisted mass fermions. Volume effects are examined using simulations at two volumes of spatial length $L=2.1$ fm and $L=2.8$ fm. Cut-off…

High Energy Physics - Lattice · Physics 2015-03-17 C. Alexandrou , M. Brinet , J. Carbonell , M. Constantinou , P. A. Harraud , P. Guichon , K. Jansen , T. Korzec , M. Papinutto

Multi-particle states with additional pions are expected to be a non-negligible source of excited-state contamination in lattice simulations at the physical point. It is shown that baryon chiral perturbation theory can be employed to…

High Energy Physics - Lattice · Physics 2017-05-30 Oliver Bar

Hadronic matrix elements of proton decay are essential ingredients to bridge the grand unification theory to low energy observables like proton lifetime. In this paper we non-perturbatively calculate the matrix elements, relevant for the…

High Energy Physics - Lattice · Physics 2014-01-22 Y. Aoki , E. Shintani , A. Soni

The extraction of hadron matrix elements in lattice QCD using the standard two- and three-point correlator functions demands careful attention to systematic uncertainties. One of the most commonly studied sources of systematic error is…

We present the nucleon axial and electromagnetic form factors using \Nf{2}{1}{1} ensembles of twisted mass fermions with clover improvement and with masses tuned to their physical values. Excited state effects are studied using several…

We present lattice QCD calculations of nucleon electromagnetic form factors using pion masses $m_\pi$ = 149, 202, and 254 MeV and an action with clover-improved Wilson quarks coupled to smeared gauge fields, as used by the…

High Energy Physics - Lattice · Physics 2014-11-20 J. R. Green , J. W. Negele , A. V. Pochinsky , S. N. Syritsyn , M. Engelhardt , S. Krieg

Accessing hadronic form factors at large momentum transfers has traditionally presented a challenge for lattice QCD simulations. Here we demonstrate how a novel implementation of the Feynman-Hellmann method can be employed to calculate…

The nucleon-pion-state contribution to QCD two-point and three-point functions relevant for lattice calculations of the nucleon electromagnetic form factors are studied in chiral perturbation theory. To leading order the results depend on a…

High Energy Physics - Lattice · Physics 2021-07-07 Oliver Bar , Haris Colic

I will review heavy baryon chiral perturbation theory for the nucleon delta degrees of freedom and then examine the recent dynamical lattice calculations of the nucleon mass from the BMW, ETM, JLQCD, LHP, MILC, NPLQCD, PACS-CS, QCDSF/UKQCD…

High Energy Physics - Lattice · Physics 2009-12-04 Andre Walker-Loud

We present the nucleon strange electromagnetic form factors using four lattice QCD ensembles with $N_f=2+1+1$ twisted mass clover-improved fermions and quark masses tuned to approximately their physical values. The four ensembles have…

We evaluate the isovector nucleon electromagnetic form factors in quenched and full QCD on the lattice using Wilson fermions. In the quenched theory we use a lattice of spatial size 3 fm at beta=6.0 enabling us to reach low momentum…

High Energy Physics - Lattice · Physics 2008-11-26 C. Alexandrou , G. Koutsou , J. W. Negele , A. Tsapalis

We present results on the electroweak form factors and on the lower moments of parton distributions of the nucleon, within lattice QCD using two dynamical flavors of degenerate twisted mass fermions. Results are obtained on lattices with…

High Energy Physics - Lattice · Physics 2012-01-04 C. Alexandrou , M. Brinet , J. Carbonell , M. Constantinou , P. Guichon , P. A. Harraud , K. Jansen , C. Kallidonis , T. Korzec , M. Papinutto

We present results on the nucleon form factors and moments of generalized parton distributions obtained within the twisted mass formulation of lattice QCD. We include a discussion of lattice artifacts by examining results at different…

High Energy Physics - Lattice · Physics 2010-12-10 C. Alexandrou , M. Constantinou , T Korzec , J. Carbonell , P. A. Harraud , M. Papinutto , P. Guichon , K. Jansen

We present results for the electromagnetic form factors of the proton and neutron computed on the Coordinated Lattice Simulations (CLS) ensembles with $N_f = 2 + 1$ flavors of $\mathcal{O}(a)$-improved Wilson fermions and an…

High Energy Physics - Lattice · Physics 2023-01-10 Miguel Salg , Dalibor Djukanovic , Georg von Hippel , Harvey B. Meyer , Konstantin Ottnad , Hartmut Wittig

We present a short summary for the calculations of the nucleon $\textit{isovector}$ form factors, which are relevant to improving the accuracy of the current neutrino oscillation experiments. The calculations are carried out with two of…

The QCDSF/UKQCD collaboration has an ongoing program to calculate nucleon matrix elements with two flavours of dynamical O(a) improved Wilson fermions. Here we present recent results on the electromagnetic form factors, the quark momentum…

High Energy Physics - Lattice · Physics 2008-11-26 M. Göckeler , Ph. Hägler , R. Horsley , Y. Nakamura , D. Pleiter , P. E. L. Rakow , A. Schäfer , G. Schierholz , W. Schroers , H. Stüben , J. M. Zanotti

We review recent results on hadron form factors and nucleon generalized parton distibutions obtained with dynamical lattice QCD simulations. We discuss lattice artifacts and open questions, and present the connection of lattice results to…

High Energy Physics - Lattice · Physics 2010-12-10 C. Alexandrou