How to probe the spin-dependent gluon distributions

Abstract

Two-spin asymmetries $A_{LL}^{{\pi }^0}$ are calculated for various types of spin-dependent gluon distributions. It is concluded that the E581/704 data on $A_{LL}^{{\pi }^0}$ do not necessarily rule out the large gluon polarization but restrict severely the $x$ dependence of its distribution. Moreover, $A_{LL}^{J/\psi }$ are calculated for the forthcoming test of spin-dependent gluon distributions.

Comments: LaTeX file, 6 pages+5 figures available upon request, KOBE-FHD-94-02, Talk delivered at meeting on "Dynamics of Quarks and Hadrons", YITP (Japan), Dec. 6-8, 1993