B to tensor meson form factors in the perturbative QCD approach

TL;DR

This paper computes B to tensor meson form factors using perturbative QCD, revealing their similarities to B to vector meson form factors and applying results to semileptonic decay predictions.

Contribution

It introduces a method to derive B to tensor meson form factors from B to vector meson form factors within the perturbative QCD framework, based on wave function similarities.

Findings

B to T form factors are smaller than B to V at q^2=0.

Form factors exhibit correlated q^2-dependence behaviors.

Predicted semileptonic decay branching fractions are around 10^{-4}.

Abstract

We calculate the $B_{u,d,s}\to T$ form factors within the framework of the perturbative QCD approach, where $T$ denotes a light tensor meson with $J^P=2^+$. Due to the similarities between the wave functions of a vector and a tensor meson, the factorization formulas of $B\to T$ form factors can be obtained from the $B\to V$ transition through a replacement rule. As a consequence, we find that these two sets of form factors have the same signs and correlated $q^2$-dependence behaviors. At $q^2=0$ point, the $B\to T$ form factors are smaller than the $B\to V$ ones, in accordance with the experimental data of radiative B decays. In addition, we use our results for the form factors to explore semilteptonic $B\to Tl\bar \nu_l$ decays and the branching fractions can reach the order $10^{-4}$.