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arXiv · hep-lat/0409137

String breaking with dynamical Wilson fermions

G. S. Bali·Th. Duessel·Th. Lippert·H. Neff·Z. Prkacin·K. Schilling
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Abstract

We present results of our ongoing determination of string breaking in full QCD with N_f=2 Wilson fermions. Our investigation of the fission of the static quark-antiquark string into a static-light meson-antimeson system is based on dynamical configurations of size 24^3 x 40 produced by the TxL collaboration. Combining various optimization methods we determine the matrix elements of the two-by-two system with so far unprecedented accuracy. The all-to-all light quark propagators occurring in the transition element are computed from eigenmodes of the Hermitian Wilson-Dirac matrix complemented by stochastic estimates in the orthogonal subspace. We observe a clear signature for level-splitting between ground state and excited potential. Thus, for the first time, string breaking induced by sea quarks is observed in a simulation of 4-dimensional lattice-QCD.

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G. S. Bali, Th. Duessel, Th. Lippert, H. Neff, Z. Prkacin, K. Schilling. 2004-09-22. String breaking with dynamical Wilson fermions. https://doi.org/10.1016/j.nuclphysbps.2004.11.305

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