Transversity distributions and Drell-Yan spin asymmetries

Abstract

We discuss transversity distributions and Drell-Yan transverse double spin asymmetries. First, the antiquark flavor asymmetry ${\Delta }_{{}_T}\bar{u}/{\Delta }_{{}_T}\bar{d}$ is discussed by using two different descriptions, a meson-cloud model and a Pauli exclusion model. We find that both calculations produce a significant ${\Delta }_{{}_T}\bar{d}$ excess over ${\Delta }_{{}_T}\bar{u}$. Next, we study its effects on the transverse spin asymmetry $A_{{}_{TT}}$ and on the Drell-Yan proton-deuteron asymmetry ${\Delta }_{{}_T}{\sigma }^{pd}/2{\Delta }_{{}_T}{\sigma }^{pp}$. We find that the ratio ${\Delta }_{{}_T}{\sigma }^{pd}/2{\Delta }_{{}_T}{\sigma }^{pp}$ is very useful for investigating the flavor asymmetry effect.

1+3 pages, LATEX with npb.sty, 2 eps figures. Talk given at the 7th International Workshop on Deep Inelastic Scattering and QCD, DESY Zeuthen, Germany, April 29 -- 23,1999, to be published in Nuclear Physics B. Complete postscript file including the figures is available at http://www2.cc.saga-u.ac.jp/saga-u/riko/physics/quantum1/structure.html Email: [email protected]

References in corpus (3)

• Flavor Asymmetry of Antiquark Distributions in the Nucleon
• Numerical solution of Q^2 evolution equation for the transversity distribution Delta_T q
• Polarized rho mesons and the asymmetry between Delta d^bar(x) and Delta u^bar(x) in the sea of the nucleon

Cited by in corpus (5)

• Prospects for Spin Physics at RHIC
• Dilepton production near partonic threshold in transversely polarized proton-antiproton collisions
• Single Hadronic-Spin Asymmetries in Weak Interaction Processes
• Accessing Transversity in Double-Spin Asymmetries at the BNL-RHIC
• Next-to-leading order QCD corrections to A_TT for prompt photon production