English
Related papers

Related papers: Nucleon Form Factors and Distribution Amplitudes i…

200 papers

A dressed-quark core contribution to nucleon electromagnetic form factors is calculated. It is defined by the solution of a Poincare' covariant Faddeev equation in which dressed-quarks provide the elementary degree of freedom and…

Nuclear Theory · Physics 2010-03-04 I. C. Cloet , G. Eichmann , B. El-Bennich , T. Klahn , C. D. Roberts

The electromagnetic form factors of nucleons are calculated using an AdS/QCD model by considering a Dirac field coupled to a vector field in the 5-dimensional AdS space. We also calculate a gravitational or energy-momentum form factor by…

High Energy Physics - Phenomenology · Physics 2009-06-30 Zainul Abidin , Carl E. Carlson

Taking into account the recent parameterizations of parton distribution functions (PDFs), % obtained in the recent time, the momentum transfer dependence of generalized parton distributions (GPDs) of nucleons is obtained in the limit $\xi…

High Energy Physics - Phenomenology · Physics 2024-11-18 O. V. Selyugin , O. V. Teryaev

We compute the electromagnetic form factors of the nucleon in quenched lattice QCD, using non-perturbatively improved Wilson fermions, and compare the results with phenomenology and chiral effective field theory.

High Energy Physics - Lattice · Physics 2010-04-06 M. Göckeler , T. R. Hemmert , R. Horsley , D. Pleiter , P. E. L. Rakow , A. Schäfer , G. Schierholz

We demonstrate that a relativistic constituent-quark model can give nucleon form factors in agreement with data for both low and high momentum transfer. The relativistic features of the model and the specific form of the wave function are…

High Energy Physics - Phenomenology · Physics 2009-10-22 Felix Schlumpf

We calculate the form factors for weak decays of $B_{(s)}$ and $D_{(s)}$ mesons to light pseudoscalar and vector mesons within a relativistic dispersion approach based on the constituent quark picture. This approach gives the form factors…

High Energy Physics - Phenomenology · Physics 2007-05-23 Dmitri Melikhov , Berthold Stech

We explore the possibility to construct higher-twist parton distributions in a nucleon at some low reference scale from convolution integrals of the light-cone wave functions (WFs). To this end we introduce simple models for the…

High Energy Physics - Phenomenology · Physics 2011-07-08 V. M. Braun , T. Lautenschlager , A. N. Manashov , B. Pirnay

We examine the radiative $\Delta \to \gamma N$ transition at the real photon point $Q^2=0$ using the framework of light-cone QCD sum rules. In particular, the sum rules for the transition form factors $G_M(0)$ and $R_{EM}$ are determined up…

High Energy Physics - Phenomenology · Physics 2008-11-26 J. Rohrwild

The electromagnetic nucleon form factors provide constraints on generalized quark distributions. Key results of the study presented here are a strong dependence of the average impact parameter of quarks on their longitudinal momentum…

High Energy Physics - Phenomenology · Physics 2009-11-11 M. Diehl

We outline the developed approach within the light-cone sum rules at the leading order for calculation of the gravitational form factors related to the nucleon valence quark combinations. The predictions for the gravitational form factor…

High Energy Physics - Phenomenology · Physics 2020-01-29 I. V. Anikin

We calculate the nucleon parameters in nuclear matter using the QCD sum rules approach in Fermi gas approximation. Terms up to 1/q^2 in the operator product expansion (OPE) are taken into account. The higher moments of the nucleon structure…

Nuclear Theory · Physics 2009-11-10 E. G. Drukarev , M. G. Ryskin , V. A. Sadovnikova , Th. Gutsche , Amand Faessler

A systematic analysis shows that the main uncertainties in the form factors are due to the twist-3 wave functions of the light mesons in the light-cone QCD sum rules. We propose an improved approach, in which the twist-3 wave functions…

High Energy Physics - Phenomenology · Physics 2009-10-31 Tao Huang , Zuo-Hong Li , Xiang-Yao Wu

A Poincar\'e-covariant quark+diquark Faddeev equation is used to compute nucleon elastic form factors on $0\leq Q^2\leq 18 \,m_N^2$ ($m_N$ is the nucleon mass) and elucidate their role as probes of emergent hadronic mass in the Standard…

The charge and magnetization distributions of the proton and neutron are encoded in their elastic electromagnetic form factors, which can be measured in elastic electron--nucleon scattering. By measuring the form factors, we probe the…

Nuclear Experiment · Physics 2011-06-15 John Arrington , Kees de Jager , Charles F. Perdrisat

We present a recent calculation of the gravitational form factors (GFFs) of proton using the light-front quark-diquark model constructed by the soft-wall AdS/QCD. The four GFFs $~A(Q^2)$ , $B(Q^2)$ , $C(Q^2)$ and $\bar{C}(Q^2)$ are…

High Energy Physics - Phenomenology · Physics 2021-08-10 Dipankar Chakrabarti , Chandan Mondal , Asmita Mukherjee , Sreeraj Nair , Xingbo Zhao

We calculate the form factors for the heavy-to-light transitions $B\rightarrow \pi,K $ by means of QCD sum rules using $\pi$ and $K$ light-cone wave functions. Higher twist contributions as well as gluonic corrections are taken into…

High Energy Physics - Phenomenology · Physics 2019-08-15 V. M. Belyaev , A. Khodjamirian , R. Rückl

Electromagnetic form factors of the nucleon from relativistic quark models are analyzed: results from null-plane projection of the Feynman triangle diagram are compared with a Bakamjian-Thomas model. The magnetic form factors of the models…

High Energy Physics - Phenomenology · Physics 2014-11-17 K. Bodoor , H. J. Weber , T. Frederico , M. Beyer

We investigate the effect of different forms of relativistic spin coupling of constituent quarks in the nucleon electromagnetic form factors. The four-dimensional integrations in the two-loop Feynman diagram are reduced to the null-plane,…

Nuclear Theory · Physics 2014-11-18 W. R. B. de Araujo , E. F. Suisso , T. Frederico , M. Beyer , H. J. Weber

This is a contribution to the review 50 Years of Quantum Chromodynamics edited by F. Gross and E. Klempt, to be published in Journal EPJC. This contribution reviews the nucleon resonance transition form factors determined from meson…

High Energy Physics - Phenomenology · Physics 2022-12-20 Volker D. Burkert

We discuss two types of contributions to hadronic form factors in QCD: hard gluon exchange and soft wave function overlap. Within the QCD sum rule approach, the hard contribution has strong numeric suppression by factor (\alpha_s/\pi) ~ 0.1…

High Energy Physics - Phenomenology · Physics 2014-11-17 A. V. Radyushkin