Generalized Parton Distributions and composite constituent quarks ∗ Sergio
نویسندگان
چکیده
An approach is proposed to calculate Generalized Parton Distributions (GPDs) in a Constituent Quark Model (CQM) scenario, considering the constituent quarks as complex systems. The GPDs are obtained from the wave functions of the non relativistic CQM of Isgur and Karl, convoluted with the GPDs of the constituent quarks themselves. The latter are modelled by using the structure functions of the constituent quark, the double distribution representation of GPDs, and a recently proposed phenomenological constituent quark form factor. The present approach permits to access a kinematical range corresponding to both the DGLAP and the ERBL regions, for small values of the momentum transfer and of the skewedness parameter. In this ∗Supported in part by GV-GRUPOS03/094, MCYT-FIS2004-05616-C02-01 and by MIUR through the funds COFIN03
منابع مشابه
ar X iv : h ep - p h / 03 11 19 7 v 1 1 4 N ov 2 00 3 Generalized Parton Distributions and the structure of the constituent quark 1
In a scenario where the constituent quarks are composite systems, Generalized Parton Distributions (GPDs) are built from wave functions to be evaluated in a Constituent Quark Model (CQM), convoluted with the GPDs of the constituent quarks themselves. The approach permits to access the full kinematical range corresponding to the DGLAP and ERBL regions, so that cross sections for deeply virtual C...
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