Direct J/psi and psi' Polarization and Cross Sections at the Tevatron
High Energy Physics - Phenomenology
2016-09-06 v1
Abstract
Transverse polarization of charmonium states, produced directly in collisions at asymptotically large transverse momentum p_t, has emerged as the most prominent test of color octet contributions and spin symmetry in quarkonium production. We present predictions for the polar angle distribution at moderate values of p_t \sim 4 - 20 GeV, covered by the Tevatron Run I data. We update the fits of NRQCD matrix elements and discuss their theoretical uncertainties. With our best fit values, no transverse polarization is expected at p_t \sim 5 GeV, but the angular distribution is predicted to change dramatically as p_t increases to 20 GeV.
Cite
@article{arxiv.hep-ph/9611218,
title = {Direct J/psi and psi' Polarization and Cross Sections at the Tevatron},
author = {M. Beneke and M. Kraemer},
journal= {arXiv preprint arXiv:hep-ph/9611218},
year = {2016}
}
Comments
11 pages, LaTeX, 3 figures included via epsf.sty