Instanton and Higher-Loop Perturbative Contributions to the QCD Sum-Rule Analysis of Pseudoscalar Gluonium
نویسنده
چکیده
Instanton effects and three-loop perturbative contributions are incorporated into QCD sum-rule analyses of pseudoscalar (JPC = 0−+) gluonium. Gaussian sumrules are shown to be superior to Laplace sum-rules in optimized predictions for pseudoscalar gluonium states in the presence of instanton contributions. The Gaussian sum-rule analysis yields a pseudoscalar mass of (2.65 ± 0.33)GeV and width bounded by Γ < 530MeV. The Laplace sum-rules provide corroborating evidence in support of the ≈ 2.7GeV mass scale.
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تاریخ انتشار 2003