Presence of the Universal Substructures in the Hadrons – Constituent Quarks
نویسنده
چکیده
The universality of single-spin asymmetry on inclusive π-meson production is discussed. This universality can be related to the hadron substructure— constituent quarks in the frame of the quark model for U-matrix. Polarization experiments give us an unique opportunity to probe the nucleon internal structure. While spin averaged cross-sections can be calculated within acceptable accuracy, current theory of strong interactions can not describe large spin asymmetries and polarization. Polarization is a precise tool for measuring the electroweak parameters, spin dependent structure functions etc. After establishing the fact that the nucleon spin is not described by simple summing of the quark spins, the study of gluonic and orbital momentum contribution to it is very important and intriguing.
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