$B\to K$ Transition Form Factor with Tensor Current within the $k_T$ Factorization Approach

TL;DR

This paper calculates the $B o K$ transition form factor with tensor current using the $k_T$ factorization approach, providing results consistent with existing sum rule calculations and analyzing key uncertainties.

Contribution

It applies the $k_T$ factorization method to the $B o K$ tensor form factor, offering a new calculation and uncertainty analysis in the large recoil region.

Findings

Obtained $F_T^{B o K}(0)=0.25\u00b10.01\u00b10.02$ consistent with sum rule results.

Identified main uncertainties from wave functions of the pion and B-meson.

Demonstrated the applicability of $k_T$ factorization to tensor form factors.

Abstract

In the paper, we apply the $k_T$ factorization approach to deal with the $B\to K$ transition form factor with tensor current in the large recoil regions. Main uncertainties for the estimation are discussed and we obtain $F_T^{B\to K}(0)=0.25\pm0.01\pm0.02$, where the first error is caused by the uncertainties from the pionic wave functions and the second is from that of the B-meson wave functions. This result is consistent with the light-cone sum rule results obtained in the literature.