Shadowing corrections to the evolution of singlet structure function

Abstract

We report a semi-analytical approach for the solution of the nonlinear Gribov-Levin-Ryskin-Mueller-Qiu (GLR-MQ) evolution equation for sea quark distribution and investigate the effect of gluon shadowing on the small-x and moderate-Q^2 behaviour of singlet structure function, F_2^S(x,Q^2). The predicted values of singlet structure functions with shadowing corrections are comparable with different experimental data as well as parametrizations. It is very fascinating to observe signatures of gluon recombination in our predictions. We note that, with decreasing x the the rapid growth of singlet structure function is eventually tamed by the shadowing or nonlinear term appeared in the QCD evolution due to gluon recombination. This taming behaviour of shadowing singlet structure function towards small-x become significant at the hot spots, at R=2 GeV^{-1}. Further the computed values of the ratio of {F_2^S(x,Q^2)} with shadowing to that without shadowing clearly indicate that towards smaller values of x and Q^2 the nonlinear effects play an increasingly important role.