2017/03/31 by Wei Cheng, W. S. Cheng, Xing-Gang Wu +1
Mathematics · Physics and Astronomy · #Geometry #High-Energy Particle Collisions Research #Mathematical physics #Mathematics #Particle physics #Particle physics theoretical and experimental studies #Physics #Quantum Chromodynamics and Particle Interactions #Twist #hep-ph
paper · pdf · doi:10.1103/physrevd.95.094023
published as Phys. Rev. D 95, 094023 (2017) · 17 pages, 6 figures. Discussions improved and references updated. To be published in Phys.Rev.D
arxiv created 2017/05/09 · openalex created_date 2017/05/19 · openalex publication_date 2017/05/30 · arxiv updated 2017/06/01 · openalex updated_date 2026/08/05
In this paper, we study the B\ensuremath→K* transition form factors (TFFs) within the QCD light-cone sum rules (LCSR) approach. Two correlators, i.e., the usual one and the right-handed one, are adopted in the LCSR calculation. The resultant LCSRs for the B\ensuremath→K* TFFs are arranged according to the twist structure of the K*-meson light-cone distribution amplitudes (LCDAs), whose twist-2, twist-3, and twist-4 terms behave quite differently by using different correlators. We observe that the twist-4 LCDAs, though generally small, shall have sizable contributions to the TFFs A1/2, V, and T1; thus, the twist-4 terms should be kept for a sound prediction. We also observe that, even though different choices of the correlator lead to different LCSRs with different twist contributions, the large correlation coefficients for most of the TFFs indicate that the LCSRs for different correlators are close to each order, not only for their values at the large recoil point q2=0 but also for their ascending trends in the whole q2 region. Such a high degree of correlation is confirmed by their application to the branching fraction of the semileptonic decay B\ensuremath→K*\ensuremathμ+\ensuremathμ^\ensuremath-. Thus, a proper choice of correlator may inversely provide a chance for probing uncertain LCDAs; i.e., the contributions from those LCDAs can be amplified to a certain degree via a proper choice of correlator, thus amplifying the sensitivity of the TFFs and, hence, their related observables, to those LCDAs.