Branching fractions of $B^-\to D^-X_{0,1}(2900)$ and their implications

TL;DR

This paper investigates the production mechanisms of the exotic states $X_{0,1}(2900)$ in B-meson decays, emphasizing the role of final-state interactions and rescattering effects to explain observed branching fractions.

Contribution

It introduces a rescattering mechanism approach to analyze the production of $X_{0,1}(2900)$ in B decays, providing new insights beyond traditional mass and width analyses.

Findings

Rescattering effects can produce large branching fractions for $B^- o D^- X_{0,1}$.

The mechanism explains observed decay rates involving $ar{ ext{b}} o ext{c}$ transitions.

Analysis of $B o DX_{0,1}$ decays can shed light on the isospin properties of $X_{0,1}$.

Abstract

The exotic states $X_{0,1}(2900)$ with the quark flavor of $cs\bar{u}\bar{d}$ are recently observed in the mass spectrum of $D^+K^-$ in $B^-\to D^-D^+K^-$ by the LHCb collaboration. To explore the nature of $X_{0,1}(2900)$, except for analyzing their masses and decay widths as usually did in literatures, the study of their production mechanism in $B$-meson weak decays would provide another important information. The amplitude of $B^-\to D^- X_{0,1}$ is non-factorizable. We consider the final-state-interaction effects and calculate them via the rescattering mechanism. The measured branching fractions of $B^-\to D^- X_{0,1}$ are revealed. It is manifested by ${B}^-\to \Lambda_c^-\Xi_c^{(\prime)0}$ and $\Lambda_b^0\to P_c^+K^-$ that the rescattering mechanism can result in the relatively large branching fractions. The similar processes of $B^-\to \pi^-X_{0,1}$ are also analyzed. The isospins of $X_{0,1}$ can be investigated by $B\to DX_{0,1}^{\pm,0}$ decays.