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Constraint on Δg(x) from π^0 production at RHIC

M. Hirai·S. Kumano·N. Saito
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Abstract

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

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M. Hirai, S. Kumano, N. Saito. 2006-12-05. Constraint on Δg(x) from π^0 production at RHIC. https://doi.org/10.1063/1.2750809

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