RT Journal Article
T1 Sketching the pion’s valence-quark generalised parton distribution
A1 Mezrag, Cédric
A1 Chang, L.
A1 Moutarde, Hervé
A1 Rodríguez Quintero, José
AB In order to learn effectively from measurements of generalised parton distributions (GPDs), it is desirableto compute them using a framework that can potentially connect empirical information with basicfeatures of the Standard Model. We sketch an approach to such computations, based upon a rainbowladder(RL) truncation of QCD’s Dyson–Schwinger equations and exemplified via the pion’s valencedressed-quark GPD, Hvπ(x, ξ, t). Our analysis focuses primarily on ξ = 0, although we also capitalise onthe symmetry-preserving nature of the RL truncation by connecting Hvπ(x, ξ = ±1, t) with the pion’svalence-quark parton distribution amplitude. We explain that the impulse-approximation used hithertoto define the pion’s valence dressed-quark GPD is generally invalid owing to omission of contributionsfrom the gluons which bind dressed-quarks into the pion. A simple correction enables us to identifya practicable improvement to the approximation for Hvπ(x, 0, t), expressed as the Radon transform ofa single amplitude. Therewith we obtain results for Hvπ(x, 0, t) and the associated impact-parameterdependent distribution, qvπ (x, | b⊥|), which provide a qualitatively sound picture of the pion’s dressedquarkstructure at a hadronic scale. We evolve the distributions to a scale ζ =2 GeV, so as to facilitatecomparisons in future with results from experiment or other nonperturbative methods.
PB Elsevier
SN 0370-2693
YR 2014
FD 2014-12
LK http://hdl.handle.net/10272/18386
UL http://hdl.handle.net/10272/18386
LA eng
NO Mezrag, C., Chang, L., Moutarde, H. ... Rodríguez Quintero, J. (2014). Sketching the pion’s valence-quark generalised parton distribution. Physics Letters B, 741, 190–196. DOI: https://doi.org/10.1016/j.physletb.2014.12.027
NO We thank A. Besse, I.C. Cloet, D. Muller, P. Fromholz, C. Keppel, P. Kroll, J.-Ph. Lansberg, C. Lorce, J. Segovia and S. Wallon for valuable discussions. C.M., L.C., H.M., C.D.R. and J.R.-Q. are grateful for the chance to participate in the workshop "Many Manifestations of Nonperturbative QCD under the Southern Cross", Ubatuba, Sao Paulo, where significant parts of this work were first presented and improvements discussed. C.D.R. acknowledges support from an International Fellow Award from the Helmholtz Association; and this research was otherwise supported by: Commissariat a l'Energie Atomique; JRA "Study of Strongly Interacting Matter" (Grant Agreement no. 283286, HadronPhysics3) under the EU Seventh Framework Programme; GDR 3034 PH-QCD; ANR-12-MONU-0008-01 "PARTONS"; University of Adelaide and Australian Research Council through grant no. FL0992247; Spanish ministry Research Project FPA2011-23781; U.S. Department of Energy, Office of Science, Office of Nuclear Physics, contract no. DE-AC02-06CH11357; and Forschungszentrum Julich GmbH.
DS Repositorio Institucional de la Universidad de Huelva
RD 15 jun 2026