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arXiv · 1701.00345

Heavy-quark meson spectrum tests of the Oktay-Kronfeld action

Jon A. Bailey·Yong-Chull Jang·Weonjong Lee·Carleton DeTar·Andreas S. Kronfeld·Mehmet B. Oktay
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Abstract

The Oktay-Kronfeld (OK) action extends the Fermilab improvement program for massive Wilson fermions to higher order in suitable power-counting schemes. It includes dimension-six and -seven operators necessary for matching to QCD through order ${\mathrm{O}}(Λ^3/m_Q^3)$ in HQET power counting, for applications to heavy-light systems, and ${\mathrm{O}}(v^6)$ in NRQCD power counting, for applications to quarkonia. In the Symanzik power counting of lattice gauge theory near the continuum limit, the OK action includes all ${\mathrm{O}}(a^2)$ and some ${\mathrm{O}}(a^3)$ terms. To assess whether the theoretical improvement is realized in practice, we study combinations of heavy-strange and quarkonia masses and mass splittings, designed to isolate heavy-quark discretization effects. We find that, with one exception, the results obtained with the tree-level-matched OK action are significantly closer to the continuum limit than the results obtained with the Fermilab action. The exception is the hyperfine splitting of the bottom-strange system, for which our statistical errors are too large to draw a firm conclusion. These studies are carried out with data generated with the tadpole-improved Fermilab and OK actions on 500 gauge configurations from one of MILC's $a\approx0.12$~fm, $N_f=2+1$-flavor, asqtad-staggered ensembles.

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Jon A. Bailey, Yong-Chull Jang, Weonjong Lee, Carleton DeTar, Andreas S. Kronfeld, Mehmet B. Oktay. 2017-01-02. Heavy-quark meson spectrum tests of the Oktay-Kronfeld action. https://doi.org/10.1140/epjc%2Fs10052-017-5266-y

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