부산대학교 도서관

We present a new calculation of the semileptonic tree-level and flavor-changing neutral current form factors describing $B$-meson transitions to tensor mesons $T=D_2^*,K_2^*,a_2,f_2$ ($J^{P}=2^{+}$). We employ the QCD Light-Cone Sum Rules approach with $B$-meson distribution amplitudes. We go beyond the leading-twist accuracy and provide analytically, for the first time, higher-twist corrections for the two-particle contributions up to twist four terms. We observe that the impact of higher twist terms to the sum rules is noticeable. We study the phenomenological implications of our results on the radiative ${B} \to K_2^{*}\gamma$ and semileptonic ${B} \to D_2^* \ell {\bar \nu}_\ell$, ${B} \to K_2^{*}\ell^+\ell^-$ decays.
Comment: 31 pages, 5 figures, 4 tables, references added, slight modifications on the text, numerical results revised using a new fit function, main conclusions unchanged. Version accepted for publication in PRD