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arXiv · hep-lat/9707013

Heavy-light decay constants---MILC results with the Wilson action

MILC Collaboration·Claude Bernard·Tom Blum·Thomas A. DeGrand·Carleton DeTar·Steven Gottlieb·Urs M. Heller·Jim Hetrick·Craig McNeile·Kari Rummukainen·A. Soni·Bob Sugar·Doug Toussaint·Matthew Wingate
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Abstract

We present the current status of our ongoing calculations of pseudoscalar meson decay constants for mesons that contain one light and one heavy quark (f_B, f_{B_s}, f_D, f_{D_s}). We are currently generating new gauge configurations that include dynamical quarks and calculating the decay constants. In addition, we have several new results for the static approximation. Those results, as well as several refinements to the analysis, are new since Lattice '96. Our current (still preliminary) value for f_B is 156 +- 11 +- 30 +- 14 MeV, where the first error is from statistical and fitting errors, the second error is an estimate of other systematic errors within the quenched approximation and the third error is an estimate of the quenching error. For the ratio f_{B_s}/f_B, we get 1.11 +- 0.02 +- 0.03 +- 0.07.

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MILC Collaboration, Claude Bernard, Tom Blum, Thomas A. DeGrand, Carleton DeTar, Steven Gottlieb, Urs M. Heller, Jim Hetrick, Craig McNeile, Kari Rummukainen, A. Soni, Bob Sugar, Doug Toussaint, Matthew Wingate. 1997-07-15. Heavy-light decay constants---MILC results with the Wilson action. https://doi.org/10.1016/s0920-5632(97)00472-6

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