Polarized hadron pair production from electron-positron annihilation

Abstract

We study the production of two almost back-to-back hadrons from the annihilation of an electron and a positron, allowing for the polarization of all particles involved. In particular, we conduct a general (model-independent) structure function decomposition of the cross section for the case $e^{+}{e}^{-}\to {\gamma }^{\ast }\to h_a{h}_{b}X$. Moreover, using the parton model we calculate the relevant structure functions in terms of twist-2 transverse momentum dependent (TMD) fragmentation functions (FFs). We also give results for the situation $e^{+}{e}^{-}\to Z^{\ast }\to h_a{h}_{b}X$ (including $\gamma$-$Z$ interference) within this model. This is the first time a complete framework has been presented for the examination of TMD FFs within $e^{+}{e}^{-}\to h_a{h}_{b}X$. We also specify certain parts of our analysis that hold for the triple-polarized semi-inclusive deep-inelastic scattering process and for di-hadron fragmentation. Furthermore, we give an explicit prescription of how our work can be translated to the Drell-Yan reaction, which provides for the first time full results for double-polarized Drell-Yan that include electroweak effects. We further discuss the relevance of our $e^{+}{e}^{-}\to h_a{h}_{b}X$ results for future experiments at $e^{+}{e}^{-}$ machines.

Comments: 29 pages, 5 figures, Version to appear in Phys. Rev. D