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Probing Relativistic Spin Effects in the Nucleon by Means of Drell-Yan Processes

F. Cano·P. Faccioli·M. Traini
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Abstract

Significant differences between transverse and longitudinal polarized parton distributions are found at low energies within a light-front covariant quark model of the nucleon. These differences are due to relativistic spin effects introduced by the Melosh rotations and survive evolution to higher $Q^2$ scales. A specific observable related to double-spin asymmetries in lepton pair production in polarized hadron-hadron collisions is defined. The possibility of assessing the relevance of these relativistic spin effects in future experiments at RHIC and HERA--$\vec{N}$ is discussed.

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F. Cano, P. Faccioli, M. Traini. 2000-11-12. Probing Relativistic Spin Effects in the Nucleon by Means of Drell-Yan Processes. https://doi.org/10.1103/physrevd.62.094018

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