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Related papers: Nucleon Axial and Electromagnetic Form Factors

200 papers

Nucleon decays put extremely stringent bounds on baryon-number-violating interactions. However, in case the corresponding operators involve only $\tau$ leptons, the direct two-body decays, e.g., $p\to\pi^0 \tau^+$, are kinematically not…

High Energy Physics - Phenomenology · Physics 2023-09-18 Andreas Crivellin , Martin Hoferichter

Recent progress on the extraction of electromagnetic properties of nucleon resonance excitation through pion photo- and electroproduction is reviewed. Cross section data measured at MAMI, ELSA, and CEBAF are analyzed and compared to the…

Nuclear Theory · Physics 2015-05-30 L. Tiator , D. Drechsel , S. S. Kamalov , M. Vanderhaeghen

The isovector axial form factor of the nucleon plays a key role in interpreting data from long-baseline neutrino oscillation experiments. We perform a lattice-QCD based calculation of this form factor, introducing a new method to directly…

High Energy Physics - Lattice · Physics 2022-07-08 Dalibor Djukanovic , Georg von Hippel , Jonna Koponen , Harvey B. Meyer , Konstantin Ottnad , Tobias Schulz , Hartmut Wittig

We present the current status of our lattice calculation of the electromagnetic form factor of the pion with two flavours of non-perturbatively O(a)-improved Wilson fermions. Using twisted boundary conditions and stochastic sources we…

High Energy Physics - Lattice · Physics 2013-01-17 Bastian B. Brandt , Andreas Juttner , Hartmut Wittig

We present results on the axial, scalar and tensor isovector-couplings of the nucleon from 2+1 flavor lattice QCD with physical light quarks ($m_\pi$ = 135 MeV) in large spatial volume of (10.8 fm)$^3$. The calculations are carried out with…

We report isovector form factors and low moments of isovector structure functions of nucleon from the coarse RIKEN-BNL-Columbia (RBC) and UKQCD joint dynamical (2+1)-flavor domain-wall fermions (DWF) ensembles. The lattice cut off is…

High Energy Physics - Lattice · Physics 2008-10-02 Shigemi Ohta , Takeshi Yamazaki

In this work, we report a novel technique in lattice QCD for studying the high momentum-transfer region of nucleon form factors. These calculations could give important theoretical input to experiments, such as those of JLab's 12-GeV…

High Energy Physics - Lattice · Physics 2010-05-06 Huey-Wen Lin , Saul D. Cohen , Robert G. Edwards , Kostas Orginos , David G. Richards

We study the imaginary parts of the isoscalar electromagnetic and isovector axial form factors of the nucleon close to the $3\pi$-threshold in covariant baryon chiral perturbation theory. At the two-loop level, the contributions arising…

Nuclear Theory · Physics 2019-03-27 N. Kaiser , E. Passemar

We use the energy-momentum tensor (EMT) current to compute the EMT form factors of the nucleon in the framework of the light cone QCD sum rule formalism. In the calculations, we employ the most general form of the nucleon's interpolating…

High Energy Physics - Phenomenology · Physics 2020-03-18 K. Azizi , U. Ozdem

We present preliminary results from the first calculation of the pion electromagnetic form factor at physical light quark masses. This form factor parameterises the deviations from the behaviour of a point-like particle when a photon hits…

High Energy Physics - Lattice · Physics 2013-11-15 Jonna Koponen , Francis Bursa , Christine Davies , Gordon Donald , Rachel Dowdall

In this paper we present the derivation as well as the numerical results for the electromagnetic form factors of the nucleon within the chiral quark soliton model in the semiclassical quantization scheme. The model is based on semibosonized…

High Energy Physics - Phenomenology · Physics 2009-10-28 Chr. V. Christov , A. Z. Górski , K. Goeke , P. V. Pobylitsa

The electromagnetic and gravitational form factors of the nucleon are studied simultaneously using a covariant quark-diquark approach, and the pion cloud effect on the form factors is explicitly discussed. In this study, the electromagnetic…

High Energy Physics - Phenomenology · Physics 2025-08-14 Jiaqi Wang , Dongyan Fu , Yubing Dong

The unitarity relations for isovector nucleon form factors in the two-pion approximation for the intermediate states are analytically extended in a model independent way from the real half-axis t > 4 $\mu^2$ ($\mu$ is the pion mass) to the…

Nuclear Theory · Physics 2007-05-23 M. I. Krivoruchenko

We present a comprehensive study of the electromagnetic form factor, the decay constant and the mass of the pion computed in lattice QCD with two degenerate O(a)-improved Wilson quarks at three different lattice spacings in the range…

High Energy Physics - Lattice · Physics 2015-06-16 Bastian B. Brandt , Andreas Juttner , Hartmut Wittig

Nucleon and pion electromagnetic form factors are evaluated in the spacelike region within a light-front constituent quark model, where eigenfunctions of a mass operator, reproducing a large set of hadron energy levels, are adopted and…

Nuclear Theory · Physics 2009-10-28 F. Cardarelli , E. Pace , G. Salme' , S. Simula

The nucleon axial form factor is a dominant contribution to errors in neutrino oscillation studies. Lattice QCD calculations can help control theory errors by providing first-principles information on nucleon form factors. In these…

High Energy Physics - Lattice · Physics 2016-10-17 Aaron S. Meyer , Richard J. Hill , Andreas S. Kronfeld , Ruizi Li , James N. Simone

The electromagnetic form factors are computed using eigenstates of linear momentum for the nucleon. The latter is described in the framework of the chiral color-dielectric model, projecting the hedgehog ansatz on eigenstates of angular…

Nuclear Theory · Physics 2009-10-30 Alessandro Drago , Manuel Fiolhais , Ubaldo Tambini

We present results on 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 obtained using…

High Energy Physics - Lattice · Physics 2021-02-04 Santanu Mondal , Rajan Gupta , Sungwoo Park , Boram Yoon , Tanmoy Bhattacharya , Huey-Wen Lin

In treating the relativistic three-quark problem, a dressed-quark propagator parameterization is used which is compatible with recent lattice data and pion observables. Furthermore two-quark correlations are modeled as a series of quark…

High Energy Physics - Phenomenology · Physics 2008-11-26 M. Oettel , R. Alkofer

We report on numerical lattice QCD calculations of some of the low moments of the nucleon structure functions. The calculations are carried out with gauge configurations generated by the RBC and UKQCD collaborations with (2+1)-flavors of…

High Energy Physics - Lattice · Physics 2014-11-20 Yasumichi Aoki , Tom Blum , Huey-Wen Lin , Shigemi Ohta , Shoichi Sasaki , Robert Tweedie , Takeshi Yamazaki , James Zanotti