$B_s\to D^{(*)}_s l\nu$ form factors using heavy HISQ quarks

McLean, Euan; Davies, C. T. H.; Lytle, Andrew; Koponen, Jonna

doi:10.22323/1.334.0281

Cited by 8 publications

(8 citation statements)

References 16 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…Heavy HISQ calculations are underway for the form factors for B ðsÞ → D Ã ðsÞ , B c → J=ψ decay, and the related B s → D s decay over the full q 2 range, using the techniques developed for c → s decays to normalize the currents nonperturbatively [51,84]. Initial results [74,99] look very promising.…”

Section: Discussionmentioning

confidence: 99%

Lattice QCD form factor for Bs→Ds*lν at zero recoil with nonperturbative current renormalization

et al. 2019

View full text Add to dashboard Cite

We present details of a lattice QCD calculation of the B s → D Ã s axial form factor at zero recoil using the highly improved staggered quark (HISQ) formalism on the second-generation MILC gluon ensembles that include up, down, strange and charm quarks in the sea. Using the HISQ action for all valence quarks means that the lattice axial vector current that couples to the W can be renormalized fully nonperturbatively, giving a result free of the perturbative matching errors that previous lattice QCD calculations have had. We calculate correlation functions at three values of the lattice spacing, and multiple b-quark masses, for physical c and s. The functional dependence on the b-quark mass can be determined and compared to heavy quark effective theory expectations, and a result for the form factor obtained at the physical value of the b-quark mass. We find F B s →D Ã s ð1Þ ¼ h s A 1 ð1Þ ¼ 0.9020ð96Þ stat ð90Þ sys. This is in agreement with earlier lattice QCD results, which use NRQCD b quarks, with a total uncertainty reduced by more than a factor of 2. We discuss implications of this result for the B → D Ã axial form factor at zero recoil and for determinations of V cb .

show abstract

Section: Discussionmentioning

confidence: 99%

Lattice QCD form factor for Bs→Ds*lν at zero recoil with nonperturbative current renormalization

et al. 2019

View full text Add to dashboard Cite

show abstract

“…This includes calculations for B → D * from JLQCD [25] with Möbius domain-wall quarks, Fermilab/MILC [40] (see also talk at Lattice 2019) with improved Wilson/Fermilab quarks and LANL/SWME with an improved version of this formalism known as the Oktay-Kronfeld action [41]. Calculations for other b → c pseudoscalar-to-vector form factors, B s → D * s [42] and B c → (J/ψ, η c ) are also underway from HPQCD [43,44] using the all-HISQ approach. At the same time further B → D and B s → D s form factor calculations are in progress, including those using a variant of the Fermilab approach known as relativistic heavy quarks on RBC/UKQCD configurations [45].…”

Section: B → D ( * ) Form Factors From Lattice Qcdmentioning

confidence: 99%

“…As mentioned above, the semileptonic moments have been analysed also including higher order power corrections estimated using the LSSA [330]. In this case a kinetic scheme fit to the experimental data that additionally includes a constraint m kin b = 4.550 (42) GeV from PDG (after scheme con-version) leads to a slightly more precise value, Inclusive semileptonic heavy to light decays can in principle be analyzed similarly to B → X c ν by using a local OPE. In practice, due to the large charm background, experimental cuts are generally imposed and reduce the "inclusivity" of the theoretical prediction.…”

Section: Determination Of |V Cb | From Inclusive Decaysmentioning

confidence: 99%

Challenges in semileptonic $${\varvec{B}}$$ decays

et al. 2020

View full text Add to dashboard Cite

Two of the elements of the Cabibbo–Kobayashi–Maskawa quark mixing matrix, $$|V_{ub}|$$ | V ub | and $$|V_{cb}|$$ | V cb | , are extracted from semileptonic B decays. The results of the B factories, analysed in the light of the most recent theoretical calculations, remain puzzling, because for both $$|V_{ub}|$$ | V ub | and $$|V_{cb}|$$ | V cb | the exclusive and inclusive determinations are in clear tension. Further, measurements in the $$\tau $$ τ channels at Belle, Babar, and LHCb show discrepancies with the Standard Model predictions, pointing to a possible violation of lepton flavor universality. LHCb and Belle II have the potential to resolve these issues in the next few years. This article summarizes the discussions and results obtained at the MITP workshop held on April 9–13, 2018, in Mainz, Germany, with the goal to develop a medium-term strategy of analyses and calculations aimed at solving the puzzles. Lattice and continuum theorists working together with experimentalists have discussed how to reshape the semileptonic analyses in view of the much higher luminosity expected at Belle II, searching for ways to systematically validate the theoretical predictions in both exclusive and inclusive B decays, and to exploit the rich possibilities at LHCb.

show abstract

“…Several lattice projects are working toward this direction. At this conference, the status is reported by RBC/UKQCD (Witzel et al [41]), JLQCD (Kaneko et al [63]), HPQCD (McLean et al [65]), Fermilab/MILC (Vaquero et al [66], see also [67]), as well as the Seoul group (Park et al [68]).…”

Section: Pos(lattice2018)008mentioning

confidence: 99%

Hints and challenges in heavy flavor physics

Hashimoto¹

2019

Proceedings of the 36th Annual International Symposium on Lattice Field Theory — PoS(LATTICE2018)

View full text Add to dashboard Cite

$B_s\to D^{(*)}_s l\nu$ form factors using heavy HISQ quarks

Cited by 8 publications

References 16 publications

Lattice QCD form factor for Bs→Ds*lν at zero recoil with nonperturbative current renormalization

Lattice QCD form factor for Bs→Ds*lν at zero recoil with nonperturbative current renormalization

Challenges in semileptonic $${\varvec{B}}$$ decays

Hints and challenges in heavy flavor physics

Contact Info

Product

Resources

About