POLARIZED J PSI PRODUCTION AT CLEO

Citation
Sw. Baek et al., POLARIZED J PSI PRODUCTION AT CLEO, Journal of the Korean Physical Society, 33(1), 1998, pp. 97-101
Citations number
21
Categorie Soggetti
Physics
ISSN journal
03744884
Volume
33
Issue
1
Year of publication
1998
Pages
97 - 101
Database
ISI
SICI code
0374-4884(1998)33:1<97:PJPPAC>2.0.ZU;2-X
Abstract
Polarizations of the prompt J/psi's produced in the e(+)e(-) annihilat ion at CLEO energy (root s = 10.58 GeV) are considered in the framewor k of the nonrelativistic quantum chromodynamics (NRQCD) factorization formalism. We find that the J/psi polarization has a strong dependence on the production mechanism. At CLEO energy, the most dominant J/psi, production mechanism throughout most of phase space is the color-sing let mechanism, e(+)e(-) --> J/psi, + gg, for which J/psi's are highly longitudinally polarized. On the other hand, the dominant J/psi produc tion mechanism at the upper endpoint of the J/psi energy distribution is the color-octet process, e(+)e(-) --> (c (c) over bar)((8)) + g, fo r which J/psi's are almost unpolarized. Thus, the measurement of the p olarization of the endpoint J/psi's is another test of the color-octet mechanism and a constraint on the NRQCD matrix elements.