First evidence for the annihilation decay mode $B^{+} \to D_{s}^{+} \phi$

TL;DR

This paper reports the first evidence for the rare hadronic annihilation decay mode B+ → D_s+ φ, measuring its branching fraction and CP asymmetry with significance above 3σ, and setting limits on related decay modes.

Contribution

The study provides the first experimental evidence for the B+ → D_s+ φ decay mode, including measurements of its branching fraction and CP asymmetry, expanding understanding of hadronic B meson decays.

Findings

Evidence for B+ → D_s+ φ decay with >3σ significance.

Measured branching fraction: (1.87^{+1.25}_{-0.73} (stat) ± 0.19 (syst) ± 0.32 (norm)) × 10^{-6}.

Set upper limits on related decay modes, e.g., B+ → D+ K*0 < 1.8 × 10^{-6} at 90% CL.

Abstract

Evidence for the hadronic annihilation decay mode $B^{+} \to D_s^{+}\phi$ is found with greater than $3\sigma$ significance. The branching fraction and \CP asymmetry are measured to be \mathcal{B}(B^{+} \to D_s^{+}\phi) &=& (1.87^{+1.25}_{-0.73}({\rm stat}) \pm 0.19 ({\rm syst}) \pm 0.32 ({\rm norm})) \times 10^{-6}, \mathcal{A}_{CP}(B^{+} \to D_s^{+}\phi) &=& -0.01 \pm 0.41 ({\rm stat}) \pm 0.03 ({\rm syst}). The last uncertainty on $\mathcal{B}(B^{+} \to D_s^{+}\phi)$ is from the branching fractions of the $B^+ \to D_s^+ \kern 0.2em\bar{\kern -0.2em D}{}^0$ normalization mode and intermediate resonance decays. Upper limits are also set for the branching fractions of the related decay modes $B^{+}_{(c)} \to D^{+}_{(s)} K^{*0}$, $B^{+}_{(c)} \to D^{+}_{(s)} \kern 0.2em\bar{\kern -0.2em K}{}^{*0}$ and ${B_c^{+} \to D^{+}_{s}\phi}$, including the result ${\mathcal{B}(B^+ \to D^+ K^{*0})} < 1.8 \times 10^{-6}$ at the 90% credibility level.