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Related papers: Nucleon form factors and O(a) Improvement

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We present results for the isovector nucleon form factors measured on a $96^4$ lattice at almost the physical pion mass with a lattice spacing of 0.085 fm in 2+1 flavor QCD. The configurations are generated with the stout-smeared…

High Energy Physics - Lattice · Physics 2018-10-24 Ken-Ichi Ishikawa , Yoshinobu Kuramashi , Shoichi Sasaki , Natsuki Tsukamoto , Akira Ukawa , Takeshi Yamazaki

We present new N_f=2 data for the nucleon generalized form factors, varying volume, lattice spacing and pion mass, down to 150 MeV. We also give an update of our direct calculation of the nucleon sigma term for a range of pion mass values…

High Energy Physics - Lattice · Physics 2013-12-04 G. S. Bali , S. Collins , B. Gläßle , M. Göckeler , J. Najjar , R. Rödl , A. Schäfer , R. Schiel , W. Söldner , A. Sternbeck , P. Wein

We present first results from the QCDSF collaboration for the kaon semileptonic decay form factors at zero momentum transfer, using two flavours of non-perturbatively O(a)-improved Wilson quarks. A lattice determination of these form…

High Energy Physics - Lattice · Physics 2008-11-26 QCDSF Collaboration , D. Brommel , R. Horsley , S. M. Morozov , Y. Nakamura , D. Pleiter , G. Schierholz , H. Stuben , J. M. Zanotti

We present the analysis of isovector axial vector nucleon form factors on a set of $N_f=2+1$ CLS ensembles with $\mathcal O(a)$-improved Wilson fermions and L\"uscher-Weisz gauge action. The set of ensembles covers a pion mass range of…

High Energy Physics - Lattice · Physics 2021-12-02 Dalibor Djukanovic , Georg von Hippel , Jonna Koponen , Harvey B. Meyer , Konstantin Ottnad , Tobias Schulz , Hartmut Wittig

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 present new parameterizations of vector and axial nucleon form factors. We maintain an excellent descriptions of the form factors at low momentum transfers, where the spatial structure of the nucleon is important, and use the Nachtman…

High Energy Physics - Experiment · Physics 2008-11-26 A. Bodek , S. Avvakumov , R. Bradford , H. Budd

Using the most general form of the baryon current, nucleon form factors, induced by isovector and isoscalar axial-vector currents, are studied in the framework of light cone QCD sum rule approach. Comparison of our results on form factors…

High Energy Physics - Phenomenology · Physics 2008-11-26 T. M. Aliev , M. Savci

We present the proton and neutron vector form factors in a convenient parametric form that is optimized for momentum transfers $\lesssim$ few GeV$^2$. The form factors are determined from a global fit to electron scattering data and precise…

High Energy Physics - Phenomenology · Physics 2020-10-23 Kaushik Borah , Richard J. Hill , Gabriel Lee , Oleksandr Tomalak

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 recent developments in lattice QCD simulations as applied in the study of hadron structure. We discuss the challenges and perspectives in the evaluation of benchmark quantities such as the nucleon axial charge and the isovector…

High Energy Physics - Lattice · Physics 2015-06-19 Constantia Alexandrou

We present results for the nucleon form factors: electric ($G_E$), magnetic ($G_M$), axial ($F_A$), induced pseudoscalar ($F_P$) and pseudoscalar ($G_P$) form factors, using the second PACS10 ensemble that is one of three sets of $2+1$…

State-of-the-art lattice QCD simulations enable the evaluation of nucleon form factors and Mellin moments with controlled systematics, yielding results with unprecedented accuracy. At the same time, new theoretical approaches are allowing…

High Energy Physics - Lattice · Physics 2024-01-30 Constantia Alexandrou , Simone Bacchio

We derive light-cone sum rules for the electromagnetic nucleon form factors including the next-to-leading-order corrections for the contribution of twist-three and twist-four operators and a consistent treatment of the nucleon mass…

High Energy Physics - Phenomenology · Physics 2013-12-16 I. V. Anikin , V. M. Braun , N. Offen

We present the first quenched lattice QCD study of the form factors relevant for the hyperon semileptonic decay Sigma -> n l nu. The momentum dependence of both axial and vector form factors is investigated and the values of all the form…

High Energy Physics - Phenomenology · Physics 2009-11-11 D. Guadagnoli , V. Lubicz , M. Papinutto , S. Simula

The nucleon axial-vector form factor, $G_A$, is critical to determine the electroweak interactions of leptons with nucleons. Important examples of processes influenced by $G_A$ are elastic (anti)neutrino-nucleon scattering and muon capture…

High Energy Physics - Phenomenology · Physics 2026-04-09 Oleksandr Tomalak , Aaron S. Meyer , Clarence Wret , Tejin Cai , Richard J. Hill , Kevin S. McFarland

We compute the nucleon axial and pseudoscalar form factors using three $N_f=$2+1+1 twisted mass fermion ensembles with all quark masses tuned to approximately their physical values. The values of the lattice spacings of these three physical…

The extrapolation of nucleon magnetic form factors calculated within lattice QCD is investigated within a framework based upon heavy baryon chiral effective-field theory. All one-loop graphs are considered at arbitrary momentum transfer and…

High Energy Physics - Phenomenology · Physics 2008-11-26 P. Wang , D. B. Leinweber , A. W. Thomas , R. D. Young

We present new parameterizations of vector and axial nucleon form factors. We maintain an excellent descriptions of the form factors at low momentum transfers ($Q^2$), where the spatial structure of the nucleon is important, and use the…

High Energy Physics - Experiment · Physics 2008-11-26 A. Bodek , S. Avvakumov , R. Bradford , H. Budd

Lattice QCD calculations of the nucleon electromagnetic form factors are of interest at both the high and low momentum transfer regions. For high momentum transfers especially there are open questions which require more intense study, such…

High Energy Physics - Lattice · Physics 2022-02-04 M. Batelaan , R. Horsley , Y. Nakamura , H. Perlt , D. Pleiter , P. E. L. Rakow , G. Schierholz , H. Stüben , R. D. Young , J. M. Zanotti

We present a high-statistics calculation of nucleon electromagnetic form factors in $N_f=2+1$ lattice QCD using domain wall quarks on fine lattices, to attain a new level of precision in systematic and statistical errors. Our calculations…