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arXiv · 1011.0571

Static-light meson-meson potentials

Gunnar Bali·Martin Hetzenegger
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Abstract

We investigate potentials between pairs of static-light mesons in Nf=2 Lattice QCD, in different spin channels. The question of attraction and repulsion is particularly interesting with respect to the X(3872) charmonium state and charged candidates such as the Z+(4430). We employ the nonperturbatively improved Sheikholeslami-Wohlert fermion and the Wilson gauge actions at a lattice spacing a approx. 0.084 fm and a pseudoscalar mass mPS approx. 760 MeV. We use stochastic all-to-all propagator techniques, improved by a hopping parameter expansion. The analysis is based on the variational method, utilizing various source and sink interpolators.

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Gunnar Bali, Martin Hetzenegger. 2010-11-02. Static-light meson-meson potentials. https://arxiv.org/abs/1011.0571

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