English

Gluon fragmentation into polarized charmonium

High Energy Physics - Phenomenology 2010-01-06 v1

Abstract

Gluon fragmentation to \chicJ(1P)\chicJ(1P) followed by single photon emission represents the dominant source of prompt J/ΨJ/\Psi's at the Tevatron for p\gtap6\GeVp_\perp \gtap 6 \GeV. Since fragmenting gluons are approximately transverse, their products are significantly polarized. We find that gluon fragmentation populates the helicity levels of \chione\chione, \chitwo\chitwo and J/ΨJ/\Psi according to D\chione(h=0):D\chione(h=1)1:1D_{\chione^{(h=0)}}: D_{\chione^{(|h|=1)}} \simeq 1:1, D\chitwo(h=0):D\chitwo(h=1):D\chitwo(h=2)1:2.9:6.0D_{\chitwo^{(h=0)}} : D_{\chitwo^{(|h|=1)}} : D_{\chitwo^{(|h|=2)}} \simeq 1:2.9:6.0 and D\J(h=0):D\J(h=1)1:3.4D_{\J^{(h=0)}} : D_{\J^{(|h|=1)}} \simeq 1:3.4. We also speculate that gluon fragmentation to the radially excited \chitwo(2P)\chitwo(2P) state followed by subsequent radiative decay could represent a large source of ψ(2S)\psi'(2S)'s and potentially resolve the ψ\psi' deficit problem. A measurement of these states' polarizations would test this idea.

Keywords

Cite

@article{arxiv.hep-ph/9408352,
  title  = {Gluon fragmentation into polarized charmonium},
  author = {Peter Cho and Sandip Trivedi and Mark Wise},
  journal= {arXiv preprint arXiv:hep-ph/9408352},
  year   = {2010}
}

Comments

11 pages with 1 uuencoded figure, CALT-68-1943, FERMILAB-PUB-94/256-T

R2 v1 2026-07-22T14:22:16.649Z