scholarly journals Estimation of the Properties of Quarks. I. Vector Quark?Quark Interaction

1970 ◽  
Vol 23 (5) ◽  
pp. 615 ◽  
Author(s):  
GB Smith ◽  
LJ Tassie
Keyword(s):  
Dirac Equation ◽  
Quark Mass ◽  
Sum Rules ◽  
Effective Interaction ◽  
Form Factors ◽  
Energy Term ◽  
Quark Interaction ◽  
Nucleon Form Factors ◽  
Potential Energy Term ◽  
The Masses

From the sum rules for hadron scattering, the nucleon form factors, and the masses of the hadrons, the properties of quarks are estimated as: 2 Ge V Jc2 ;:; quark mass ;:; 30 Ge V Jc2, 0�1 fm ;:; range of the quark-quark interaction ;:; 0�25 fm. The hadrons are described by a relativistic independent quark model using the Dirac equation with a potential energy term for the effective interaction.

scholarly journals Estimation of the Properties of Quarks. II. Scalar Quark?Quark Interaction

1970 ◽  
Vol 23 (5) ◽  
pp. 627 ◽  
Author(s):  
GB Smith
Keyword(s):  
Dirac Equation ◽  
Quark Model ◽  
Quark Mass ◽  
Effective Interaction ◽  
Scalar Potential ◽  
Quark Interaction ◽  
Scalar Quark ◽  
Hadronic Spectrum

Describing the hadrons by a relativistic independent quark model, using the Dirac equation with a scalar potential for the effective interaction, the range of the quark-quark interaction is found to lie between O� 3 and 0�4 fm. The hadronic spectrum is shown to be independent of the quark mass and the form of the quark-quark interaction.

scholarly journals Light-cone sum rules for the nucleon form factors

2002 ◽  
Vol 65 (7) ◽  
Author(s):  
V. M. Braun ◽  
A. Lenz ◽  
N. Mahnke ◽  
E. Stein
Keyword(s):  
Light Cone ◽  
Sum Rules ◽  
Form Factors ◽  
Nucleon Form Factors

scholarly journals Mass sum rules of the electron in quantum electrodynamics

2020 ◽  
Vol 2020 (9) ◽  
Author(s):  
S. Rodini ◽  
A. Metz ◽  
B. Pasquini
Keyword(s):  
Quantum Electrodynamics ◽  
Rest Frame ◽  
Energy Momentum Tensor ◽  
Sum Rules ◽  
Form Factors ◽  
Momentum Tensor ◽  
Moving Frame ◽  
Nucleon Mass ◽  
Loop Order ◽  
The Masses

Abstract Different decompositions of the nucleon mass, in terms of the masses and energies of the underlying constituents, have been proposed in the literature. We explore the corresponding sum rules in quantum electrodynamics for an electron at one-loop order in perturbation theory. To this aim we compute the form factors of the energy-momentum tensor, by paying particular attention to the renormalization of ultraviolet divergences, operator mixing and scheme dependence. We clarify the expressions of all the proposed sum rules in the electron rest frame in terms of renormalized operators. Furthermore, we consider the same sum rules in a moving frame, where they become energy decompositions. Finally, we discuss some implications of our study on the mass sum rules for the nucleon.

Perturbative evolution in holographic soft-wall model

2015 ◽  
Vol 30 (11) ◽  
pp. 1550046 ◽  
Author(s):  
Majid Dehghani
Keyword(s):  
Sum Rules ◽  
Form Factors ◽  
Distribution Functions ◽  
Parton Distribution Functions ◽  
Wall Model ◽  
Hadronic Physics ◽  
Soft Wall Model ◽  
Qualitative Level ◽  
Soft Wall ◽  
Nucleon Form Factors

Generalized parton distribution functions (GPDs) describe different features of hadronic physics in a single framework. There are sum rules that relate them to phenomenologically interesting quantities. By means of GPDs calculated in the holographic soft-wall model, perturbative effects are entered into the formalism in an effective way. Using the DGLAP-like equations, GPDs are evolved to the next-to-leading order of approximation and then implications on nucleon form factors and their charge distributions will be discussed at a qualitative level.

scholarly journals Electromagnetic nucleon form factors from QCD sum rules

2005 ◽  
Vol 2005 (03) ◽  
pp. 012-012 ◽  
Author(s):  
H Castillo ◽  
C.A Dominguez ◽  
M Loewe
Keyword(s):  
Sum Rules ◽  
Form Factors ◽  
Qcd Sum Rules ◽  
Nucleon Form Factors

scholarly journals Light-cone sum rules for proton decay

2021 ◽  
Vol 2021 (5) ◽  
Author(s):  
Ulrich Haisch ◽  
Amando Hala
Keyword(s):  
Lattice Qcd ◽  
Light Cone ◽  
Sum Rules ◽  
State Of The Art ◽  
Form Factors ◽  
Baryon Number ◽  
Proton Decay ◽  
Matrix Elements ◽  
Decay Channels ◽  
Systematic Uncertainties

Abstract We estimate the form factors that parametrise the hadronic matrix elements of proton-to-pion transitions with the help of light-cone sum rules. These form factors are relevant for semi-leptonic proton decay channels induced by baryon-number violating dimension-six operators, as typically studied in the context of grand unified theories. We calculate the form factors in a kinematical regime where the momentum transfer from the proton to the pion is space-like and extrapolate our final results to the regime that is relevant for proton decay. In this way, we obtain estimates for the form factors that show agreement with the state-of-the-art calculations in lattice QCD, if systematic uncertainties are taken into account. Our work is a first step towards calculating more involved proton decay channels where lattice QCD results are not available at present.

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