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Two Topics in QCD Sum-Rules: Bounds on Light Quark and Scalar Gluonium Masses

T. G. Steele·D. Harnett
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Abstract

QCD Laplace sum-rules are briefly reviewed and two sum-rule applications are presented. For scalar gluonium, upper bounds on the lightest state are obtained from ratios of Laplace sum-rules, and the role of instantons and the low-energy theorem on these bounds is investigated. For the light-quark masses, fundamental inequalities for Laplace sum-rules are developed, which lead to a lower bound on the average of the up and down quark masses.

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T. G. Steele, D. Harnett. 2001-08-28. Two Topics in QCD Sum-Rules: Bounds on Light Quark and Scalar Gluonium Masses. https://arxiv.org/abs/hep-ph/0108232

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