Instanton effects in twist-3 generalized parton distributions
Oct 25, 20236 pages
Published in:
- Phys.Lett.B 848 (2024) 138387
- Published: Dec 7, 2023
e-Print:
- 2310.16890 [hep-ph]
DOI:
- 10.1016/j.physletb.2023.138387 (publication)
Report number:
- JLAB-THY-23-3946
View in:
Citations per year
Abstract: (Elsevier B.V.)
The instanton vacuum picture is used to study hadronic matrix elements of the twist-3 (dimension-4, spin-1) QCD operators measuring the quark spin density and spin-orbit correlations. The QCD operators are converted to effective operators in the low-energy effective theory emerging after chiral symmetry breaking, in a systematic approach based on the diluteness of the instanton medium and the expansion. The instanton fields induce spin-flavor-dependent “potential” terms in the effective operators, complementing the “kinetic” terms from the quark field momenta. As a result, the effective operators obey the same equation-of-motion relations as the original QCD operators. The spin-orbit correlations are qualitatively different from naive quark model expectations.Note:
- 6 pages, 1 figure
- instanton: effect
- twist: 3
- quantum chromodynamics: operator
- expansion 1/N: color
- symmetry breaking: chiral
- quark: spin: density
- generalized parton distribution
- effective operator
- correlation
- quark model
References(18)
Figures(1)
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