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arXiv · hep-ph/0212192

The strong coupling constant at small momentum as an instanton detector

Ph. Boucaud·F. De Soto·A. Le Yaouanc·J. P. Leroy·J. Micheli·H. Moutarde·O. Pène·J. Rodríguez-Quintero
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Abstract

We present a study of $α_{MOM}(p)$ at small p computed from the lattice. It shows a dramatic $\propto p^4$ law which can be understood within an instanton liquid model. In this framework the prefactor gives a direct measure of the instanton density in thermalised configurations. A preliminary result for this density is 5.27(4) fm^{-4}.

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Ph. Boucaud, F. De Soto, A. Le Yaouanc, J. P. Leroy, J. Micheli, H. Moutarde, O. Pène, J. Rodríguez-Quintero. 2002-12-13. The strong coupling constant at small momentum as an instanton detector. https://doi.org/10.1088/1126-6708%2F2003%2F04%2F005

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