Constraint on {delta}g(x) from {pi}0 production at RHIC
We determine the polarized gluon distribution {delta}g(x) by a global analysis using current DIS and {pi}0 asymmetry data. The {pi}0 data from RHIC-Spin experiments provide a strong constraint on {delta}g(x), so that its uncertainty is reduced. However, a sign problem appears in the analysis using {pi}0 data, which means that positive and negative distributions are allowed for {delta}g(x). These two types of solutions are discussed.