Decays of B, B_s and B_c to D-wave heavy–light mesons

We study the weak decays of B¯ _{( s )} and B_c into D-wave heavy–light mesons, including J^P= 2 ^- (D(s)2,D(s)2′,B(s)2,B(s)2′) and 3 ^- (D(s)3∗,B(s)3∗) states. The weak decay hadronic matrix elements are obtained based on the instantaneous Bethe–Salpeter method. The branching ratios for the B¯ decays are B[B¯→D2eν¯e]=1.1+0.3-0.3×10-3, B[B¯→D2′eν¯e]=4.1+0.9-0.8×10-4, and B[B¯→D3∗eν¯e]=1.0+0.2-0.2×10-3, respectively. For the semi-electronic decays of B¯ _s to D_{s 2}, Ds2′, and Ds3∗, the corresponding branching ratios are 1.7+0.5-0.5×10-3, 5.2+1.6-1.5×10-4, and 1.5+0.4-0.4×10-3, respectively. The branching ratios of the semi-electronic decays of B_c to D-wave D mesons are in the order of 10 ^{- 5}. We also obtained the forward–backward asymmetry, angular spectra, and lepton momentum spectra. In particular the distribution of decay widths for the 2 ^- states D₂ and D2′ varying along with mixing angle are presented.