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Related papers: Nucleon Isovector Axial Form Factors

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We present results on the nucleon scalar, axial and tensor charges as well as on the momentum fraction, and the helicity and transversity moments. The pion momentum fraction is also presented. The computation of these key observables is…

We extract the isovector tensor nucleon form factors, which play an important role in understanding the transverse spin structure of the nucleon when related to the quark helicity-flip generalized parton distributions via their first…

High Energy Physics - Phenomenology · Physics 2011-10-10 Guray Erkol , Altug Ozpineci

We report a high precision calculation of the isospin vector charge $g_{S,T}$ of the nucleon using recently proposed ``blending" method which provides a high-precision stochastic estimate of the all-to-all fermion propagator. Through…

High Energy Physics - Lattice · Physics 2026-03-03 Ji-Hao Wang , Zhi-Cheng Hu , Xiangdong Ji , Xiangyu Jiang , Yushan Su , Peng Sun , Yi-Bo Yang

We present high statistics results for the structure of the nucleon from a mixed-action calculation using 2+1 flavors of asqtad sea and domain wall valence fermions. We perform extrapolations of our data based on different chiral effective…

The electromagnetic form factors of the nucleon are calculated in an extended chiral constituent-quark model where the effective interaction is described by the exchange of pseudoscalar, vector, and scalar mesons. Two-body current-density…

High Energy Physics - Phenomenology · Physics 2007-05-23 P. Demetriou , S. Boffi , M. Radici , R. F. Wagenbrunn

At the TeV scale, low-energy precision observations of neutron characteristics provide unique probes of novel physics. Precision studies of neutron decay observables are susceptible to beyond the Standard Model (BSM) tensor and scalar…

High Energy Physics - Lattice · Physics 2023-12-15 R. E. Smail , M. Batelaan , R. Horsley , Y. Nakamura , H. Perlt , D. Pleiter , P. E. L. Rakow , G. Schierholz , H. Stüben , R. D. Young , J. M. Zanotti

The electromagnetic form factors of the nucleon have been calculated in a chiral constituent-quark model. The nucleon wave functions are obtained by solving a Schr\"odinger-type equation for a semi-relativistic Hamiltonian with an effective…

High Energy Physics - Phenomenology · Physics 2009-10-31 S. Boffi , P. Demetriou , M. Radici , R. F. Wagenbrunn

We determine the generalized form factors, which correspond to the second Mellin moment (i.e., the first $x$-moment) of the generalized parton distributions of the nucleon at leading twist. The results are obtained using lattice QCD with…

High Energy Physics - Lattice · Physics 2019-07-30 Gunnar S. Bali , Sara Collins , Meinulf Göckeler , Rudolf Rödl , Andreas Schäfer , André Sternbeck

We consider the axial-vector together with its induced pseudo-scalar form factor of the nucleon as computed from the chiral Lagrangian with nucleon and isobar degrees of freedom. The form factors are evaluated at the one-loop level, where…

High Energy Physics - Phenomenology · Physics 2024-04-05 Felix Hermsen , Tobias Isken , David Thoma , Matthias F. M. Lutz

Current status of nucleon structure calculations with joint RBC and UKQCD 2+1-flavor dynamical domain-wall fermions (DWF) lattice QCD is reported: Two ensembles with pion mass of about (m_\pi=170) MeV and 250 MeV are used. The lattice…

High Energy Physics - Lattice · Physics 2019-08-13 Shigemi Ohta

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

High statistics results for the isovector momentum fraction, $\langle x \rangle_{u-d}$, helicity moment, $\langle x \rangle_{\Delta u-\Delta d}$, and the transversity moment, $\langle x\rangle_{\delta u-\delta d}$, of the nucleon are…

High Energy Physics - Lattice · Physics 2021-06-11 Santanu Mondal , Rajan Gupta , Sungwoo Park , Boram Yoon , Tanmoy Bhattacharya , Bálint Joó , Frank Winter

We calculate the electromagnetic, axial and pseudo-scalar form factors of the Nucleon to $\Delta(1232)$ transition using two dynamical light degenerate quarks and a dynamical strange quark simulated with the domain wall fermion action.…

High Energy Physics - Lattice · Physics 2011-02-25 C. Alexandrou , G. Koutsou , J. W. Negele , Y. Proestos , A. Tsapalis

Nucleon form factors are calculated on q^2 in [0,3] GeV^2 using an Ansatz for the nucleon's Fadde'ev amplitude motivated by quark-diquark solutions of the relativistic Fadde'ev equation. Only the scalar diquark is retained, and it and the…

Nuclear Theory · Physics 2009-01-14 J. C. R. Bloch , C. D. Roberts , S. M. Schmidt , A. Bender , M. R. Frank

The nucleon axial-vector coupling constant $g_A$ is studied in the presence of an external magnetic field, and in dense nuclear environments, to emulate nuclear matter in magnetars. For this purpose we use QCD finite energy sum rules for…

High Energy Physics - Phenomenology · Physics 2024-06-24 C. A. Dominguez , Marcelo Loewe , Cristian Villavicencio , R. Zamora

We present state-of-the-art results for the matrix elements of flavor diagonal tensor operators within the nucleon state. The calculation of the dominant connected contribution is done using eleven ensembles of gauge configurations…

High Energy Physics - Lattice · Physics 2018-12-05 Rajan Gupta , Boram Yoon , Tanmoy Bhattacharya , Vincenzo Cirigliano , Yong-Chull Jang , Huey-Wen Lin

Using the most general form of the nucleon interpolating current, we calculate the tensor form factors of the nucleon within light cone QCD sum rules. A comparison of our results on tensor form factors with those of the chiral--soliton…

High Energy Physics - Phenomenology · Physics 2015-05-30 T. M. Aliev , K. Azizi , M. Savci

A new method of obtaining the strange form factors of the nucleon is presented, in which forward-angle parity-violating $\vec{e}p$ elastic scattering data is combined with $\nu p$ and $\bar{\nu} p$ elastic scattering data. The axial form…

High Energy Physics - Experiment · Physics 2007-05-23 Stephen F. Pate

The axial form factor G_A of the nucleon is investigated for the Goldstone-boson-exchange constituent quark model using the point-form approach to relativistic quantum mechanics. The results, being covariant, show large contributions from…

Nuclear Theory · Physics 2009-11-07 L. Ya. Glozman , M. Radici , R. F. Wagenbrunn , S. Boffi , W. Klink , W. Plessas

We compute the axial, scalar, tensor and pseudoscalar isovector couplings of the nucleon as well as the induced tensor and pseudoscalar charges in lattice simulations with $N_f=2$ mass-degenerate non-perturbatively improved…