Charmed and light pseudoscalar meson decay constants from four-flavor lattice QCD with physical light quarks

Abstract

We compute the leptonic decay constants f D + , f Ds , and f K + , and the quark-mass ratios m c /m s and m s /m l in unquenched lattice QCD using the experimentally determined value of f π + for normalization. We use the MILC Highly Improved Staggered Quark ( |V cs | = 1.010(5)(18)(6), where the errors are from this calculation of the decay constants, the uncertainty in the experimental decay rates, structure-dependent electromagnetic corrections, and, in the case of |V us |, the uncertainty in |V ud |, respectively.

Heavy Flavors

“…3 The left-hand side of Eq. (2.2) is known from experiment to about 8% while lattice has determined FNAL/MILC [13] ETM [16] TWQCD [15] |V…”

“…Recent lattice works include a calculation by FNAL/MILC [13] using the MILC N f = 2+1+1 HISQ configurations with HISQ valence physical-mass light and charm quarks at 0.06, 0.09, 0.12, and 0.15 fm. They are also calculating [14] both D and B decay constants using MILC N f = 2 + 1 asqtad configurations with asqtad light quarks and Fermilab charm/bottom quarks.…”

“…ETM [18] FNAL/MILC [13] TWQCD [15] ETM [16] Figure 2: Recent lattice results are shown in magenta (FNAL/MILC [13], TWQCD [15], and ETM [16,18]). Previous year's results, and their averages, are shown in gray and are taken from FLAG [7].…”

“…They plan to form ratios of form factors with D (s) decay constants to cancel charm quark discretization effects, then combine the ratios with the high-precision results of Ref. [13]. A separate effort by FNAL/MILC [31] uses the MILC N f = 2 + 1 + 1 HISQ ensembles, HISQ valence quarks, three lattice spacings (0.06, 0.09, and 0.12 fm), and physical quark masses.…”

“…ETM [18] FNAL/MILC [13] ETM [16] TWQCD [15] 0.95 1.00 1.05 Figure 5: Recent lattice results from FNAL/MILC [13], ETM [16,18], TWQCD [15], and HPQCD [33] are shown in magenta. Previous year's results are shown in gray and are taken from FLAG [7].…”