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B-meson decay constant from unquenched lattice QCD
Alan Gray1, Matthew Wingate, Christine T H Davies
1Department of Physics, The Ohio State University, Columbus, Ohio 43210, USA.
Physical Review Letters
|December 31, 2005
Summary
We calculated the B-meson decay constant, f(B), and the ratio f(B)(s)/f(B) using advanced lattice quantum chromodynamics simulations with unquenched gauge configurations. Our results provide precise values for these fundamental particle physics parameters.
Area of Science:
- * High Energy Physics
- * Quantum Chromodynamics
- * Hadron Spectroscopy
Background:
- * B-meson decay constants are crucial for understanding weak interactions and testing the Standard Model.
- * Previous calculations were limited by approximations in quark masses and lattice actions.
Purpose of the Study:
- * To determine the B-meson decay constant, f(B), with improved accuracy.
- * To calculate the ratio of strange to non-strange B-meson decay constants, f(B)(s)/f(B).
- * To leverage advanced lattice QCD techniques for precise results.
Main Methods:
- * Utilized MILC Collaboration's unquenched gauge configurations with three flavors of light sea quarks.
- * Employed nonrelativistic QCD for heavy quarks and the AsqTad staggered quark action for light valence and sea quarks.
- * Performed chiral extrapolation using the good chiral properties of the AsqTad action.
Main Results:
- * Determined the B-meson decay constant f(B) = 216(9)(19)(4)(6) MeV.
- * Calculated the ratio f(B)(s)/f(B) = 1.20(3)(1).
Conclusions:
- * The study provides precise determinations of key B-meson decay constants.
- * The methods employed allow for more accurate chiral extrapolations compared to previous studies.
- * Results contribute to refining theoretical predictions in particle physics.
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