Study of $D^{**}$ production and light hadronic states in the $\bar{B}^0 \to D^{*+} ����^-$ decay

We report on the first observations of $\bar{B}^0 \to D_1(2430)^0 ��$, $\bar{B}^0 \to D_1(2420)^0 ��$ and $\bar{B}^0 \to D^*_2(2460)^0 ��$ decays. The $\bar{B}^0 \to D^{*+} ��(1450)^-$ decay is also observed. The branching fraction measurements are based on $(771.6 \pm 10.6)\times 10^6$ $B\bar{B}$ events collected at the $��(4S)$ resonance with the Belle detector at the KEKB asymmetric-energy $e^+e^-$ collider. The fractions of longitudinal polarization of the $D^{**}$ states as well as partial wave fractions of the $D_1(2430)^0$ are obtained. We also set a $90\%$ confidence level upper limit for the product of branching fractions of $\mathcal{B}(\bar{B}^0 \to D^{*+} b_1(1235)^-) \times \mathcal{B}(b_1(1235)^- \to ����^-)$. The measurements show evidence of nontrivial final-state interaction phases for the $��$-like amplitudes.
29 pages, 12 figures, submitted to Physical Review D