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Related papers: Nucleon axial-vector and pseudoscalar form factors…

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The D-term is one of the conserved charges of hadrons defined as the forward limit of the gravitational form factor $D(t)$. We calculate the nucleon's D-term in a holographic QCD model in which the nucleon is described as a soliton in five…

High Energy Physics - Theory · Physics 2022-09-27 Mitsutoshi Fujita , Yoshitaka Hatta , Shigeki Sugimoto , Takahiro Ueda

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 of pion and nucleon are considered within the framework of the Quark-Gluon Strings Model, where the dependence of the form factors on $q^2$ is determined by the intercept of a dominant Regge trajectory and…

High Energy Physics - Phenomenology · Physics 2009-08-25 A. B. Kaidalov , L. A. Kondratyuk , D. V. Tchekin

We present a study of proton and neutron electromagnetic form factors for the recently proposed Goldstone-boson-exchange constituent quark model. Results for charge radii, magnetic moments, and electric as well as magnetic form factors are…

Nuclear Theory · Physics 2009-11-06 R. F. Wagenbrunn , S. Boffi , W. Klink , W. Plessas , M. Radici

We study the nucleon and diquarks in a non-local Nambu-Jona-Lasinio model. For certain parameters the model exhibits quark confinement, in the form of a propagator without real poles. After truncation of the two-body channels to the scalar…

High Energy Physics - Phenomenology · Physics 2009-11-10 Amir H. Rezaeian , Niels R. Walet , Michael C. Birse

Relativistic, kinematically complete phenomenological expressions for the dilepton decay rates of nucleon resonances with arbitrary spin and parity are derived in terms of the magnetic, electric, and Coulomb transition form factors. The…

Nuclear Theory · Physics 2011-08-17 M. I. Krivoruchenko , B. V. Martemyanov , Amand Faessler , C. Fuchs

We calculate the electric dipole form factor of the neutron in a perturbative chiral quark model, parameterizing CP-violation of generic origin by means of effective electric dipole moments of the constituent quarks and their CP-violating…

High Energy Physics - Phenomenology · Physics 2008-11-26 Claudio Dib , Amand Faessler , Thomas Gutsche , Sergey Kovalenko , Jan Kuckei , Valery E. Lyubovitskij , Kem Pumsa-ard

The RQCD collaboration proposed a projection method to remove the excited state contamination in lattice OCD calculations of nuclear form factors. The effectiveness of this method in removing the two-particle nucleon-pion-state…

High Energy Physics - Lattice · Physics 2020-02-28 Oliver Bar

We determine the nucleon axial, scalar and tensor charges at the continuum limit by analyzing three $N_f=2+1+1$ twisted mass fermion ensembles with all quark masses tuned to approximately their physical values. We include all contributions…

High Energy Physics - Lattice · Physics 2025-02-11 Constantia Alexandrou , Simone Bacchio , Jacob Finkenrath , Christos Iona , Giannis Koutsou , Yan Li , Gregoris Spanoudes

We explain how the emergent phenomenon of dynamical chiral symmetry breaking ensures that Poincar\'e covariant analyses of the three valence-quark scattering problem in continuum quantum field theory yield a picture of the nucleon as a…

Nuclear Theory · Physics 2018-04-04 Jorge Segovia , Cédric Mezrag , Lei Chang , Craig D. Roberts

We study the electromagnetic structure of the nucleon within a hybrid constituent-quark model that comprises, in addition to the $3q$ valence component, also a $3q$+$\pi$ non-valence component. To this aim we employ a Poincar\'e-invariant…

High Energy Physics - Phenomenology · Physics 2016-04-20 Daniel Kupelwieser , Wolfgang Schweiger

A quark model relation between the neutron charge form factor and the N->Delta charge quadrupole form factor is used to predict the C2/M1 ratio in the N->Delta transition from the elastic neutron form factor data. Excellent agreement with…

High Energy Physics - Phenomenology · Physics 2007-05-23 A. J. Buchmann

Dyson-Schwinger equation treatments of the strong interaction show that the presence and importance of nonpointlike diquark correlations within the nucleon are a natural consequence of dynamical chiral symmetry breaking. Using this…

Nuclear Theory · Physics 2015-06-16 Craig D. Roberts , Roy J. Holt , Sebastian M. Schmidt

Analyses of the three valence-quark bound-state problem in relativistic quantum field theory predict that the nucleon may be understood primarily as a Borromean bound-state, in which binding arises mainly from two separate effects. One…

Nuclear Theory · Physics 2015-09-30 Jorge Segovia , Craig D. Roberts , Sebastian M. Schmidt

A formalism based on a relativistic plane wave impulse approximation is developed to investigate the strange-quark content ($g_{A}^{s}$) of the axial-vector form factor of the nucleon via neutrino-nucleus scattering. Nuclear structure…

Nuclear Theory · Physics 2008-11-26 B. I. S. van der Ventel , J. Piekarewicz

We re-investigate Adler's PCAC relation in the presence of an external electromagnetic field within the framework of QCD coupled to external fields. We discuss pion electroproduction within a tree-level approximation to chiral perturbation…

Nuclear Theory · Physics 2009-11-10 T. Fuchs , S. Scherer

In the present paper we extend the Schwinger model of the nucleon to the inclusion of loop corrections. Starting from a chiral model of nucleon and delta for the mesons $\pi,\rho$ and $A_1$ we extend our nonperturbative sefconsistent…

High Energy Physics - Phenomenology · Physics 2007-05-23 C. Arias Tobena , M. F. Gari

We construct the full axial current of the constituent quarks by a summation of the infinite number of diagrams describing constituent-quark soft interactions. By requiring that the conservation of this current is violated only by terms of…

High Energy Physics - Phenomenology · Physics 2007-05-23 Wolfgang Lucha , Dmitri Melikhov , Silvano Simula

The charge form factor and weak decay constant of the pion as well as the pion-quark coupling constant in symmetric nuclear matter are explored in the framework of the Nambu--Jona-Lasinio model, where the pion is described as a bound state…

Nuclear Theory · Physics 2019-01-16 Parada T. P. Hutauruk , Yongseok Oh , K. Tsushima

We analyze the CP-violating electric dipole form factor of the nucleon in the framework of covariant baryon chiral perturbation theory. We give a new upper bound on the vacuum angle, |\theta_0| \lesssim 2.5 \cdot 10^{-10}. The quark mass…

High Energy Physics - Phenomenology · Physics 2010-05-07 K. Ottnad , B. Kubis , U. -G. Meißner , F. -K. Guo
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