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arXiv · 1411.4676

Variational method with staggered fermions

Carleton DeTar·Song-Haeng Lee
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Abstract

The variational method is used widely for determining eigenstates of the QCD hamiltonian for actions with a conventional transfer matrix, e.g., actions with improved Wilson fermions. An alternative lattice fermion formalism, staggered fermions, does not have a conventional single-time-step transfer matrix. Nonetheless, with a simple modification, the variational method can also be applied to that formalism. In some cases the method also provides a mechanism for separating the commonly paired parity-partner states. We discuss the extension to staggered fermions and illustrate it by applying it to the calculation of the spectrum of charmed-antistrange mesons consisting of a clover charm quark and a staggered strange antiquark.

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Carleton DeTar, Song-Haeng Lee. 2014-11-17. Variational method with staggered fermions. https://doi.org/10.1103/physrevd.91.034504

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