Observation of the decays $B^{+} \to \Sigma_{c}(2455)^{++} \overline{\Xi}_{c}^{-}$ and $B^{0} \to \Sigma_{c}(2455)^{0} \overline{\Xi}_{c}^{0}$

TL;DR

This paper reports the first observation of specific two-body baryonic B meson decays, measuring their branching fractions with high statistical significance using data from Belle and Belle II detectors.

Contribution

The study presents the first observation and measurement of the branching fractions of the decays $B^{+} o \Sigma_{c}(2455)^{++} ar{\Xi}_{c}^{-}$ and $B^{0} o \\Sigma_{c}(2455)^{0} ar{\Xi}_{c}^{0}$, expanding knowledge of baryonic B decays.

Findings

First observation of the two decay modes with significances over 6 sigma.

Measured branching fractions are approximately 5.74 and 4.83 times 10^{-4}.

Results are based on data collected at the \\Upsilon(4S) resonance by Belle and Belle II.

Abstract

We report the first observation of the two-body baryonic decays $B^{+} \to \Sigma_{c}(2455)^{++} \overline{\Xi}_{c}^{-}$ and $B^{0} \to \Sigma_{c}(2455)^{0} \overline{\Xi}_{c}^{0}$ with significances of $7.3\,\sigma$ and $6.2\,\sigma$, respectively, including statistical and systematic uncertainties. The branching fractions are measured to be $\mathcal{B}(B^{+} \to \Sigma_{c}(2455)^{++} \overline{\Xi}_{c}^{-}) = (5.74 \pm 1.11 \pm 0.42_{-1.53}^{+2.47}) \times 10^{-4}$ and $\mathcal{B}(B^{0} \to \Sigma_{c}(2455)^{0} \overline{\Xi}_{c}^{0}) = (4.83 \pm 1.12 \pm 0.37_{-0.60}^{+0.72}) \times 10^{-4}$. The first and second uncertainties are statistical and systematic, respectively, while the third ones arise from the absolute branching fractions of $\overline{\Xi}_{c}^{-}$ or $\overline{\Xi}_{c}^{0}$ decays. The data samples used for this analysis have integrated luminosities of 711~$\mathrm{fb}^{-1}$ and 365~$\mathrm{fb}^{-1}$, and were collected at the $\Upsilon(4S)$ resonance by the Belle and Belle~II detectors operating at the KEKB and SuperKEKB asymmetric-energy $e^{+}e^{-}$ colliders, respectively.