Gluonic contribution toB→η(′)form factors

Abstract

We calculate the flavor-singlet contribution to the B → η (′) transition form factors from the gluonic content of the η (′) meson in the large-recoil region using the perturbative QCD approach. The formulation for the η-η ′ mixing in the quark-flavor and singlet-octet schemes is compared, and employed to determine the chiral enhancement scales associated with the two-parton twist-3 η (′) meson distribution amplitudes. It is found that the gluonic contribution is negligible in the B → η form factors, and reaches few percents in the B → η ′ ones. Its impact on the accommodation of the measured B → η (′) K branching ratios in the perturbative QCD and QCD-improved factorization approaches is elaborated.

Form factors of B, Bs → η (′) and D, Ds → η (′) transitions from QCD light-cone sum rules

“…We see that the dominant errors in M → η form factors is coming from the variation of b η ( ),g 2 and it amounts to about 15%, while in M → η decays come to 2%. Our findings for calculated B → η ( ) form factors agree very well with those from [16,[39][40][41]. Their q-dependence of the form factors and their ratios is shown in figures 4-9.…”

η−η′mixing: From electromagnetic transitions to weak decays of charm and beauty hadrons

“…In the pQCD approach the impact of the gluonic component on the branching ratiopotentially important since it increases the branching ratios B → η ′ K, while decreasing the B → K η one -has been estimated to be numerically very small [88]. The phenomenological importance of the η ′ gluonic content was instead emphasized in the contest of SCET [89].…”

B→η(′)(l−ν¯l,lAkeroyd1, Chen2, Geng3 2007Phys. Rev. D362370View full textAdd to dashboardCite

“…In this paper, inspired by the measurements of the semileptonic decays, we would like to propose another possible mechanism within the quark-flavor mixing scheme to study the decays of B → η (′) (ℓ −ν ℓ , ℓ + ℓ − , K, K * ). We will also compare our results with those in the FSM [10,12,13,14,15] and explore the differences between the two mechanisms, which could be tested in future B experiments.…”