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arXiv · hep-ph/9708454

QCD Sum Rules and the Pi(1300) Resonance

T. G. Steele·J. C. Breckenridge·M. Benmerrouche·V. Elias·A. H. Fariborz
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Abstract

Global fits to the shape of the first QCD Laplace sum rule exhibiting sensitivity to pion-resonance [$Π(1300)$] parameters are performed, leading to predictions for the pion-resonance mass and decay constant. Two scenarios are considered which differ only in their treatment of the dimension-six quark condensate $< O_6>$. The first scenario assumes an effective scale for $< O_6>$ from other sum-rule applications which is assumed to be independent of the physical value of the quark mass, while the second scenario requires self-consistency between the value of $< O_6>$ and the current algebra constraint $2m< \bar q q>=-f_π^2m_π^2$. Predictions of the pion-resonance mass $M_π$ and decay constant $F_π$ are obtained in these two scenarios. A byproduct of this analysis is a prediction of the renormalization-group invariant quark mass $(\hat m_u+\hat m_d)/2$.

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T. G. Steele, J. C. Breckenridge, M. Benmerrouche, V. Elias, A. H. Fariborz. 1997-08-25. QCD Sum Rules and the Pi(1300) Resonance. https://doi.org/10.1016/s0375-9474(97)00472-7

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