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arXiv · 1511.00970

Testing the Witten-Veneziano Formula on the Lattice

Krzysztof Cichy·Elena Garcia-Ramos·Karl Jansen·Konstantin Ottnad·Carsten Urbach
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Abstract

In this proceeding contribution we report on a test of the famous Witten-Veneziano formula using lattice techniques. We perform dedicated quenched simulations and apply the spectral projector method to determine the topological susceptibility in pure Yang-Mills theory. In order to compute the relevant meson masses and the flavor singlet decay constant we employ lattice QCD with $N_f=2+1+1$ dynamical Wilson twisted mass fermions. Taking the continuum and the $SU(2)$ chiral limits we find good agreement within uncertainties for both sides of the formula.

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Krzysztof Cichy, Elena Garcia-Ramos, Karl Jansen, Konstantin Ottnad, Carsten Urbach. 2015-11-03. Testing the Witten-Veneziano Formula on the Lattice. https://arxiv.org/abs/1511.00970

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