Study of Resonances in Exclusive B Decays to Dbar(*)D(*)K

TL;DR

This paper investigates resonances in exclusive B meson decays to Dbar(*)D(*)K, reporting new observations of specific decay channels and an enhancement near 3875 MeV/c^2, with detailed measurements and spin analyses.

Contribution

It provides the first observation of certain B decay channels involving D_s1(2536), psi(3770), and an enhancement near 3875 MeV/c^2, including measurements of branching fractions and resonance properties.

Findings

Observation of B → Dbar(*) D_s1(2536) decays

Observation of B → ψ(3770) K decays

Detection of an enhancement at 3875 MeV/c^2 in Dbar*0 D^0 invariant mass

Abstract

We present a study of resonances in exclusive decays of $B$ mesons to $\bar{D}^{(*)} D^{(*)} K$. We report the observation of the decays $B \to \Dbar^{(*)} D^+_{s1}(2536)$ where the $D^+_{s1}(2536)$ is reconstructed in the $D^{*0}K^+$ and $D^{*+} K^0_S$ decay channels. We report also the observation of the decays $B \to \psi(3770) K$ where the $\psi(3770)$ decays to $\Dbar^0 D^0$ and $D^- D^+$. In addition, we present the observation of an enhancement for the $\Dbar^{*0} D^0$ invariant mass in the decays $B \to \Dbar^{*0} D^0 K$, at a mass of $(3875.1 {}^{+0.7}_{-0.5} \pm 0.5)$ MeV/$c^2$ with a width of $(3.0 {}^{+1.9}_{-1.4} \pm 0.9)$ MeV (the first errors are statistical and the second are systematic). Branching fractions and spin studies are shown for the three resonances. The results are based on 347 fb$^{-1}$ of data collected with the BaBar detector at the PEP-II $B$ factory.