Zeitschrift für Physik C Particles and Fields

, Volume 45, Issue 4, pp 669–676 | Cite as

Transversely polarized parton densities, their evolution and their measurement

  • X. Artru
  • M. Mekhfi
Article
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Abstract

The transverse spin asymmetry of a quark in a baryon and the linear polarization of a gluon in a vector meson are studied from thet-channel point of view. Using the Altarelli-Parisi approach, they are shown to obey independent evolution equations and to decrease with increasingQ2. We investigate the possibility to measure them at leading twist, to leading order in α and αs and without analyzing the final polarizations. This requires simultaneous polarization of the beam and the target; the observable effect is in the azimuthal distribution of the highP T particle or jet. Assuming a simple (quark+scalar diquark) model for the baryon, a large asymmetry is expected inp\(\bar p\) Drell-Yan collisions, a smaller one in highP T pp collisions, from the interference term in the scattering of two identical quarks.

Keywords

Evolution Equation Particle Acceleration Linear Polarization Vector Meson Observable Effect 
These keywords were added by machine and not by the authors. This process is experimental and the keywords may be updated as the learning algorithm improves.
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Copyright information

© Springer-Verlag 1990

Authors and Affiliations

  • X. Artru
    • 1
  • M. Mekhfi
    • 2
  1. 1.Laboratoire de Physique Théorique et Hautes EnergiesUniversité de Paris XIOrsayFrance
  2. 2.Laboratoire de Physique ThéoriqueUniversité d'Oran Es-SeniaOran Es-Senia 31Algéria

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