Extraction of axial form factors fromB0→D+K−K*0decay

Abstract

Based on $\overline{B}\ensuremath{\rightarrow}{D}^{(*)}{K}^{\ensuremath{-}}{K}^{*0}$ decay data, which supports factorization, we propose to extract the kaon axial form factor in the factorization framework. Experiment indicates that the ${K}^{\ensuremath{-}}{K}^{*0}$ pair is produced by an axial current where only one out of three axial form factors is dominant. The axial form factor can be extracted by fitting the ${K}^{\ensuremath{-}}{K}^{*0}$ mass spectrum with an ${a}_{1}(1260)$-resonance plus QCD-motivated nonresonant contributions, which can be improved as data improves.