2018/08/31 by Wei Cheng, W. S. Cheng, Xing-Gang Wu +3
Chemistry · Physics and Astronomy · #Chemistry #Crystallography #High-Energy Particle Collisions Research #Meson #Particle physics #Particle physics theoretical and experimental studies #Physics #Quantum Chromodynamics and Particle Interactions #hep-ph
paper · pdf · doi:10.1103/physrevd.98.096013
published as Phys. Rev. D 98, 096013 (2018) · 11 pages, 7 figures, 8 tables
openalex created_date 2018/09/07 · arxiv created 2018/10/17 · openalex publication_date 2018/11/21 · arxiv updated 2018/11/26 · openalex updated_date 2026/08/05
We study the B\ensuremath→\ensuremathρ helicity form factors (HFFs) by applying the light-cone sum rules (LCSR) up to twist-4 accuracy. The HFF has some advantages in comparison to the conventionally calculated transition form factors; e.g., the HFF parametrization can be achieved via diagonalizable unitarity relations, etc. At the large recoil point, only the \ensuremathρ-meson longitudinal component contributes to the HFFs, and we have H_\ensuremathρ,0(0)=0.435_\ensuremath-0.045+0.055 and H_\ensuremathρ,1,2(0)\ensuremath≡0. We extrapolate the HFFs to the physically allowable q2 region and apply them to the B\ensuremath→\ensuremathρ semileptonic decay. We observe that the \ensuremathρ-meson longitudinal component dominates its differential decay width in the low-q2 region, and its transverse component dominates the high-q2 region. Two ratios, Rlow and Rhigh, are used to characterize those properties, and our LCSR calculation gives Rlow=0.967_\ensuremath-0.285+0.308 and Rhigh=0.219_\ensuremath-0.070+0.058, which agree with the BABAR measurements within errors.