Nuclear Gluon Distributions in a Parton Model

Abstract

Gluon distributions in the carbon and tin nuclei are investigated by using a $Q^2$ rescaling model with parton recombination effects. We obtain strong shadowings in the small $x$ region due to the recombinations. The ratio $G_A(x)/G_N(x)$ in the medium $x$ region is typically 0.9 for medium size nuclei. At large $x$, the ratio becomes large due to gluon fusions from different nucleons. Comparisons with recent New Muon Collaboration data for $G_{Sn}(x)/G_C(x)$ indicate that more accurate experimental data are needed for testing the model.

Comments: TEX file (10 pages); Figs.1-3 (TOPDRAWER) can be obtained from the author upon request; preprint IU/NTC 92-21 (PL,B298,171(1993))