Improved Vcs determination using precise lattice QCD form factors for D→Kℓν
Apr 20, 202127 pages
Published in:
- Phys.Rev.D 104 (2021) 3, 034505
- Published: Aug 1, 2021
e-Print:
- 2104.09883 [hep-lat]
DOI:
- 10.1103/PhysRevD.104.034505 (publication)
Experiments:
View in:
Citations per year
Abstract: (APS)
We provide a 0.8%-accurate determination of from combining experimental results for the differential rate of semileptonic decays with precise form factors that we determine from lattice QCD. This is the first time that has been determined with an accuracy that allows its difference from 1 to be seen. Our lattice QCD calculation uses the highly improved staggered quark (HISQ) action for all valence quarks on gluon field configurations generated by the MILC Collaboration that include the effect of , , , and HISQ quarks in the sea. We use eight gluon field ensembles with five values of the lattice spacing ranging from 0.15 fm to 0.045 fm and include results with physical quarks for the first time. Our calculated form factors cover the full range of the physical decay process and enable a Standard Model test of the shape of the differential decay rate as well as the determination of from a correlated weighted average over bins. We obtain , where the uncertainties come from lattice QCD, experiment, short-distance electroweak, and electromagnetic corrections, respectively. This last uncertainty, neglected for hitherto, now needs attention if the uncertainty on is to be reduced further. We also determine values in good agreement using the measured total branching fraction and the rates extrapolated to . Our form factors enable tests of lepton flavor universality violation. We find the ratio of branching fractions for with and in the final state to be in the Standard Model, with the uncertainty dominated by that from electromagnetic corrections.Note:
- 27 pages, 28 figures. Small changes to text to improve readability. Updated to include the BES average for the D to K branching fraction from 2104.08081
- correction: electromagnetic
- decay: form factor: calculated
- quark: staggered
- quark: valence
- lepton: universality: violation
- lepton: flavor: universality
- branching ratio: ratio
- lattice field theory
- gluon
- electroweak interaction
References(77)
Figures(30)
- [1]
- [2]
- [3]
- [4]
- [5]
- [6]
- [7]
- [8]
- [9]
- [10]
- [11]
- [12]
- [13]
- [14]
- [15]
- [16]
- [17]
- [18]
- [19]
- [20]
- [21]
- [21]
- [21]
- [22]
- [23]