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arXiv · 1003.1937

Tuning Fermilab Heavy Quarks in 2+1 Flavor Lattice QCD with Application to Hyperfine Splittings

C. Bernard·C. DeTar·M. Di Pierro·A. X. El-Khadra·R. T. Evans·E. D. Freeland·E. Gámiz·Steven Gottlieb·U. M. Heller·J. E. Hetrick·A. S. Kronfeld·J. Laiho·L. Levkova·P. B. Mackenzie·J. N. Simone·R. Sugar·D. Toussaint·R. S. Van de Water
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Abstract

We report the non-perturbative tuning of parameters--- kappa_c, kappa_b, and kappa_crit ---that determine the heavy-quark mass in the Fermilab action. This requires the computation of the masses of Ds^(*) and Bs^(*) mesons comprised of a Fermilab heavy quark and a staggered light quark. Additionally, we report the hyperfine splittings for Ds and Bs mesons as a cross-check of our simulation and analysis methods. We find a splitting of 145 +/- 15 MeV for the Ds system and 40 +/- 9 MeV for the Bs system. These are in good agreement with the Particle Data Group average values of 143.9 +/- 0.4 MeV and 46.1 +/- 1.5 MeV, respectively. The calculations are carried out with the MILC 2+1 flavor gauge configurations at three lattice spacings $a$ approximately 0.15, 0.12, and 0.09 fm.

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C. Bernard, C. DeTar, M. Di Pierro, A. X. El-Khadra, R. T. Evans, E. D. Freeland, E. Gámiz, Steven Gottlieb, U. M. Heller, J. E. Hetrick, A. S. Kronfeld, J. Laiho, L. Levkova, P. B. Mackenzie, J. N. Simone, R. Sugar, D. Toussaint, R. S. Van de Water. 2010-03-09. Tuning Fermilab Heavy Quarks in 2+1 Flavor Lattice QCD with Application to Hyperfine Splittings. https://doi.org/10.1103/physrevd.83.034503

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