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Light hadron spectroscopy on the lattice with the non-perturbatively improved Wilson action

D. Becirevic·Ph. Boucaud·L. Giusti·J. P. Leroy·V. Lubicz·G. Martinelli·F. Mescia·F. Rapuano
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Abstract

We present results for the light meson masses and decay constants as obtained from calculations with the non-perturbatively improved (`Alpha') action and operators on a 24^3 \times 64 lattice at beta = 6.2, in the quenched approximation. The analysis was performed in a way consistent with O(a) improvement. We obtained: reasonable agreement with experiment for the hyperfine splitting; f_K=156(17) MeV, f_pi =139(22) MeV, f_K/f_pi = 1.13(4) ; f_{K*}=219(7) MeV, f_rho =199(15) MeV, f_phi =235(4) MeV; f_{K*}^{T}(2 GeV) = 178(10) MeV, f_rho^{T}(2 GeV) =165(11) MeV, where f_V^{T} is the coupling of the tensor current to the vector mesons; the chiral condensate <\bar{q}q>^\bar{MS} (2 GeV)= - (253 +/- 25 MeV)^3. Our results are compared to those obtained with the unimproved Wilson action. We also verified that the free-boson lattice dispersion relation describes our results very accurately for a large range of momenta.

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D. Becirevic, Ph. Boucaud, L. Giusti, J. P. Leroy, V. Lubicz, G. Martinelli, F. Mescia, F. Rapuano. 1998-09-16. Light hadron spectroscopy on the lattice with the non-perturbatively improved Wilson action. https://arxiv.org/abs/hep-lat/9809129

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