Constraint on ∆g(x) from π0 production at RHIC

نویسندگان

  • M. Hirai
  • S. Kumano
  • N. Saito
چکیده

We determine the polarized gluon distribution ∆g(x) by a global analysis using current DIS and π0 asymmetry data. The π0 data from RHIC-Spin experiments provide a strong constraint on ∆g(x), so that its uncertainty is reduced. However, a sign problem appears in the analysis using π0 data, which means that positive and negative distributions are allowed for ∆g(x). These two types of solutions are discussed.

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تاریخ انتشار 2008