English

Color-octet mechanism and J/psi polarization at LEP

High Energy Physics - Phenomenology 2009-10-30 v2

Abstract

Polarized heavy quarkonium productions in Z0Z^0 decays are considered. We find that polarizations of the produced quarkonia are independent of that of the parent Z^0 provided that one considers the energy distribution or the total production rate. Produced J/psi's via the color-octet and the color- singlet mechanisms are expected to be 19% and 29% longitudinally polarized, respectively. The energy dependence of eta_{1,8}(x)=\frac{dGamma_{1,8}^L}{dx} /\frac{dGamma_{1,8}}{d x} is very sensitive to the production mechanism, and therefore the measurement of \eta(x)_exp will be an independent probe of the color-octet mechanism.

Keywords

Cite

@article{arxiv.hep-ph/9701208,
  title  = {Color-octet mechanism and J/psi polarization at LEP},
  author = {Seungwon Baek and P. Ko and Jungil Lee and H. S. Song},
  journal= {arXiv preprint arXiv:hep-ph/9701208},
  year   = {2009}
}

Comments

15 pages, minor changes, version to be published in Phys. Rev. D