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$B rightarrow T$ transition form factors in light-cone sum rules

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 نشر من قبل Ahmet Kokulu
 تاريخ النشر 2019
  مجال البحث
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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 ${B} to D_2^* ell {bar u}_ell$, ${B} to K_2^{*}ell^+ell^-$ decays.



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