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Vacuum fluctuations of \bar{q}q and values of low-energy constants

S. Descotes·J. Stern
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Abstract

We discuss the influence of the vacuum fluctuations of \bar{q}q pairs on low-energy constants and condensates. The analysis of the Goldstone boson masses and decay constants shows that the three-flavour condensate and some low-energy constants are very sensitive to the value of L_6, which measures the Zweig-rule violation in the scalar channel. A chiral sum rule based on experimental data in this channel is used to constrain L_6, confirming a significant decrease between the two- and the three-flavor condensates.

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S. Descotes, J. Stern. 2000-08-18. Vacuum fluctuations of \bar{q}q and values of low-energy constants. https://doi.org/10.1016/s0370-2693(00)00897-2

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