GLUON FRAGMENTATION INTO POLARIZED CHARMONIUM

Gluon fragmentation to χcJ(1P) followed by single photon emission represents the dominant source of prompt J/ψ's at the Fermilab Tevatron for p6 GeV. Since fragmenting gluons are approximately transverse, their products are significantly polarized. We find that gluon fragmentation populates the helicity levels of χc1, χc2, and J/ψ according to Dχc1(h=0):Dχc1(=1) 1:1, Dχc2(h=0): Dχc2(=1):Dχc2(=2) 1:2.8:6.0, and DJ/ψ(h=0):DJ/ψ(=1)1:3.4. We also speculate that gluon fragmentation to the radially excited χc2(2P) state followed by radiative decay could represent a large source of ψ'(2S)'s. A measurement of these states' polarizations would test this idea. © 1995 The American Physical Society.