Semileptonic B decays into excited charmed mesons from QCD sum rules
  Exclusive semileptonic $B$ decays into excited charmed mesons are studied with QCD sum rules in the leading order of heavy quark effective theory. Two universal Isgur-Wise functions \tau and \zeta for semileptonic B decays into four lowest lying excited $D$ mesons ($D_1$, $D_2^*$, $D'_0$, and $D'_1$) are determined. The decay rates and branching ratios for these processes are calculated. 
Yuan-ben Dai(ITP,CAS), Ming-qiu Huang(CCAST & Ihep,CAS)