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arXiv · hep-lat/9801038

B Meson Decay Constants From NRQCD

A. Ali Khan·T. Bhattacharya·S. Collins·C. T. H. Davies·R. Gupta·C. Morningstar·J. Shigemitsu·J. Sloan
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Abstract

We present quenched results for B meson decay constants using NRQCD b quarks and O(a) tadpole improved clover light quarks. For the first time, one-loop matching factors between lattice and continuum currents are incorporated through O(α/M) taking operator mixing fully into account. This includes an important O(αa) discretization correction to the heavy-light axial vector current. We find f_B = 0.147(11)(^{+8}_{-12})(9)(6) MeV and f_{B_s}/f_B = 1.20(4)(^{+4}_{-0}). PACS numbers: 12.38.Gc, 12.39.Hg, 13.20.He, 14.40.Nd

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A. Ali Khan, T. Bhattacharya, S. Collins, C. T. H. Davies, R. Gupta, C. Morningstar, J. Shigemitsu, J. Sloan. 1998-04-01. B Meson Decay Constants From NRQCD. https://doi.org/10.1016/s0370-2693(98)00323-2

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