On QCD and $ω-ρ$ mixing

N. F. Nasrallah

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arXiv · hep-ph/9903223

On QCD and $ω-ρ$ mixing

N. F. Nasrallah

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Abstract

The evaluation of sum rules and vacuum condensates used in the calculation of the mixing parameters of the $ω-ρ$ system involve dangerous cancellations of large numbers. In this note the contribution of the continuum is eliminated in order to avoid such a large source of uncertainty. It is also seen that the hypothesis of vacuum saturation used in the estimate of the dimension 6 condensate is inadequate. The value obtained for the parameter $β$ which governs the off-shell variation of the $ω-ρ$ mixing is $β=.25$.

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N. F. Nasrallah. 1999-03-30. On QCD and $ω-ρ$ mixing. https://arxiv.org/abs/hep-ph/9903223

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