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A toy model for generalised parton distributions Cudell, Jean-René ; ; Cugnon, Joseph et al in AIP Conference Proceedings (2005), 775 Detailed reference viewed: 34 (3 ULg)A model for the generalized parton distribution of the pion Stassart, Pierre ; ; Cudell, Jean-René et al in AIP Conference Proceedings (2005), 756 Detailed reference viewed: 20 (3 ULg)Generalized parton distributions of the pion ; Cudell, Jean-René ; Cugnon, Joseph et al in Nuclear Physics B-Proceedings Supplements (2004, July), 133 Off-forward structure functions of the pion are investigated in twist-two and twist-three approximation. A simple model is used for the pion, which allows to introduce finite size effects, while ... [more ▼] Off-forward structure functions of the pion are investigated in twist-two and twist-three approximation. A simple model is used for the pion, which allows to introduce finite size effects, while preserving gauge invariance. Results for the imaginary parts of the gamma*pi --> gamma*pi off-forward amplitude and of the structure functions are presented. Generalized Callan-Gross relations are obtained. [less ▲] Detailed reference viewed: 21 (8 ULg)A model for the off-forward structure functions of the pion ; Cudell, Jean-René ; Cugnon, Joseph et al in Physics Letters B (2004), 587(3-4), 189-200 We extend our model for the pion, which we used previously to calculate its diagonal structure function, to the off-forward case. The imaginary part of the off-forward y*pi -->. gamma*pi scattering ... [more ▼] We extend our model for the pion, which we used previously to calculate its diagonal structure function, to the off-forward case. The imaginary part of the off-forward y*pi -->. gamma*pi scattering amplitude is evaluated in the chiral limit (m(pi) = 0) and related to the twist-two and twist-three generalised parton distributions H, H-3, (H) over tilde (3). Non-perturbative effects, linked to the size of the pion and still preserving gauge invariance, are included. Remarkable new relations between H, H3 and (H) over tilde (3) are obtained and discussed. (C) 2004 Published by Elsevier B.V. [less ▲] Detailed reference viewed: 17 (3 ULg)A simple model for generalised parton distributions of the pion Lansberg, Jean-Philippe ; ; Cudell, Jean-René et al in Bruncko, D.; Ferencei, J.; Strizenec, P. (Eds.) 12th International Workshop On Deep Inelastic Scattering (DIS 2004) (2004) Detailed reference viewed: 13 (1 ULg)Pion Structure Function and violation of the Momentum Sum Rule Lansberg, Jean-Philippe ; ; Cudell, Jean-René et al in Blin, A. H.; Hiller, B.; Ruivo, M. C. (Eds.) et al Hadron Physics: Effective Theories of Low Energy QCD N°2 (2003) We present a method to evaluate the pion structure functions from a box diagram calculation. Pion and constituent quark fields are coupled through the simplest pseudoscalar coupling. The gamma^* pi -> q ... [more ▼] We present a method to evaluate the pion structure functions from a box diagram calculation. Pion and constituent quark fields are coupled through the simplest pseudoscalar coupling. The gamma^* pi -> q \bar q cross-section is evaluated and related to the structure functions. We then show that the introduction of non-perturbative effects, related to the pion size and preserving gauge invariance, provides us with a straighforward relation with the quark distribution. It is predicted that higher-twist terms become negligible for Q^2 larger than about 2 GeV^2 and that quarks in the pion have a momentum fraction smaller than in the proton. We enlarge the discussion concerning this violation of the momentum sum rule, emphasizing that the sum rule is recovered in the chiral limit and also when the finite size condition is not imposed. [less ▲] Detailed reference viewed: 61 (3 ULg)Confinement and cut-off: A model for the Pion Quark Distribution Function Stassart, Pierre ; ; Cudell, Jean-René et al (2003) The pion structure function is investigated in a simple pseudo-scalar coupling model of pion and constituent quark fields. The imaginary part of the forward Compton scattering amplitude is evaluated. We ... [more ▼] The pion structure function is investigated in a simple pseudo-scalar coupling model of pion and constituent quark fields. The imaginary part of the forward Compton scattering amplitude is evaluated. We show that the introduction of non-perturbative effects, linked through a cut-off to the size of the pion, allows the reproduction of important features of the pion quark distribution function. [less ▲] Detailed reference viewed: 24 (14 ULg)A model for the pion structure function ; Cudell, Jean-René ; Cugnon, Joseph et al in Physics Letters B (2002), 547(3-4), 210-218 The pion structure function is investigated in a simple model, where pion and constituent quark fields are coupled through the simplest pseudoscalar coupling. The imaginary part of the forward gamma*pi ... [more ▼] The pion structure function is investigated in a simple model, where pion and constituent quark fields are coupled through the simplest pseudoscalar coupling. The imaginary part of the forward gamma*pi --> gamma*pi evaluated and related to the structure functions. It is shown that the introduction of non-perturbative effects linked to the size of the pion and preserving gauge invariance, allows a connection with the quark distribution. It is predicted that higher-twist terms become negligible for Q(2) larger than similar to 2 GeV2 and that quarks in the pion have a momentum fraction smaller than in the proton case. (C) 2002 Elsevier Science B.V. All rights reserved. [less ▲] Detailed reference viewed: 37 (14 ULg)The Valence Quark Distribution of the Pion Lansberg, Jean-Philippe ; ; Cudell, Jean-René et al in Dong Su; Burchat, Patricia (Eds.) XXII Physics in Collision Conference (PIC02) (2002) Detailed reference viewed: 32 (5 ULg) |
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