  Exclusive semi-leptonic decay stands as a pivotal channel in the exploration
of heavy flavor physics, primarily due to its straightforward experimental
measurability. In this work, we delve into the hadron matrix element and hadron
tensor within the context of exclusive semi-leptonic decays. We challenge the
conventional exclusive decay theory by introducing a fresh perspective,
revealing that while the baryon sector is consistent, the meson sector warrants
revision. Employing a novel form factor derived from the Taylor series
expansion in our differential width calculations, we demonstrate that fitting
experimental data necessitates a more streamlined and minimal parameter set
compared to the standard Light Cone Sun Rul(LCSR) form factors. Furthermore, we
propose that our hypothesis can be empirically validated or refuted through the
precise measurement of the double differential decay width, offering a tangible
path forward for experimental validation.
