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Title: Model study of generalized parton distributions with helicity flip

Abstract

Generalized parton distributions with helicity flip are studied in the quark sector, within a simple version of the MIT bag model, assuming an SU(6) wave function for the proton target. In the framework under scrutiny, it turns out that only the generalized transversity distribution, H{sub T}{sup q}, is nonvanishing. For this quantity, the forward limit is properly recovered and numerical results are found to underestimate recent lattice data for its first moment. Positivity bounds recently proposed are fulfilled by the obtained distribution. The relevance of the analysis for the planning of measurements of the quark generalized transversity is addressed.

Authors:
 [1]
  1. Dipartimento di Fisica, Universita degli Studi di Perugia, and INFN, Sezione di Perugia, via A. Pascoli, 06100 Perugia (Italy)
Publication Date:
OSTI Identifier:
20774473
Resource Type:
Journal Article
Resource Relation:
Journal Name: Physical Review. D, Particles Fields; Journal Volume: 72; Journal Issue: 11; Other Information: DOI: 10.1103/PhysRevD.72.117502; (c) 2005 The American Physical Society; Country of input: International Atomic Energy Agency (IAEA)
Country of Publication:
United States
Language:
English
Subject:
72 PHYSICS OF ELEMENTARY PARTICLES AND FIELDS; BAG MODEL; DISTRIBUTION; GLUONS; HELICITY; PROTONS; QUARKS; SU-6 GROUPS; WAVE FUNCTIONS

Citation Formats

Scopetta, Sergio. Model study of generalized parton distributions with helicity flip. United States: N. p., 2005. Web. doi:10.1103/PhysRevD.72.117502.
Scopetta, Sergio. Model study of generalized parton distributions with helicity flip. United States. doi:10.1103/PhysRevD.72.117502.
Scopetta, Sergio. Thu . "Model study of generalized parton distributions with helicity flip". United States. doi:10.1103/PhysRevD.72.117502.
@article{osti_20774473,
title = {Model study of generalized parton distributions with helicity flip},
author = {Scopetta, Sergio},
abstractNote = {Generalized parton distributions with helicity flip are studied in the quark sector, within a simple version of the MIT bag model, assuming an SU(6) wave function for the proton target. In the framework under scrutiny, it turns out that only the generalized transversity distribution, H{sub T}{sup q}, is nonvanishing. For this quantity, the forward limit is properly recovered and numerical results are found to underestimate recent lattice data for its first moment. Positivity bounds recently proposed are fulfilled by the obtained distribution. The relevance of the analysis for the planning of measurements of the quark generalized transversity is addressed.},
doi = {10.1103/PhysRevD.72.117502},
journal = {Physical Review. D, Particles Fields},
number = 11,
volume = 72,
place = {United States},
year = {Thu Dec 01 00:00:00 EST 2005},
month = {Thu Dec 01 00:00:00 EST 2005}
}
  • Several positivity bounds are derived for generalized parton distributions (GPDs) with helicity flip.
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  • We study the generalized parton distributions, including the helicity-fiip ones, using the Nambu-Jona-Lasinio (NJL) model based on a relativistic Faddeev approach with 'static approximation'. Sum rules relating the generalized parton distributions to nucleon electromagnetic form factors are satisfied. Moreover, quark-antiquark contributions in the region -{xi}<x<{xi} are nonvanishing. Our results are qualitatively similar to those calculated with Radyushkin's double distribution ansatz using forward parton distribution functions calculated in the NJL model as inputs.