Study of the charmed baryonic decays $\bar{B}^0\to\Sigma_c^{++}\bar{p}\pi^-$ and $\bar{B}^0\to\Sigma_c^{0}\bar{p}\pi^+$

TL;DR

This paper measures branching fractions of specific charmed baryonic B meson decays using Belle data, providing new insights into decay dynamics and resonance contributions in these processes.

Contribution

It reports the first precise measurements of branching fractions for several $ar{B}^0$ decay modes involving $oldsymbol{ ext{Sigma}_c}$ resonances and non-resonant contributions, with improved statistical significance.

Findings

Measured branching fractions for $ar{B}^0$ decays to $ ext{Sigma}_c(2455)$ and $ ext{Sigma}_c(2520)$ states.

Set an upper limit on the $ ext{Sigma}_c(2520)^0$ decay mode.

Determined the total branching fraction for $ar{B}^0 o ext{Lambda}_c^+ar{p} ext{pi}^+ ext{pi}^-$.

Abstract

We study the three-body charmed baryonic decays $\bar{B}^0\to\Sigma_c^{++} \bar{p}\pi^-$ and $\bar{B}^0\to\Sigma_c^{0}\bar{p}\pi^+$ in the four-body final state $\bar{B}^0\to\Lambda_c^{+}\bar{p}\pi^+\pi^-$, using a data sample of 357 fb$^{-1}$ accumulated at the $\Upsilon(4S)$ resonance with the Belle detector at the KEKB asymmetric-energy $e^+e^-$ collider. We measure the branching fractions ${\cal B} (\bar{B}^0\to\Sigma_c(2455)^{++}\bar{p}\pi^-)$=$(2.1\pm0.2\pm0.3\pm0.5)\times 10^{-4}$, ${\cal B}(\bar{B}^0\to\Sigma_c(2455)^{0}\bar{p}\pi^+)$=$(1.4\pm0.2\pm0.2\pm0.4)\times1 0^{-4}$, ${\cal B}(\bar{B}^0\to\Sigma_c(2520)^{++} \bar{p}\pi^-)$=$(1.2\pm\0.1\pm0.2\pm0.3)\times10^{-4}$ with statistical significances of 13.1, 9.5 and 7.2 standard deviations, respectively. The errors are statistical, systematic, and due to the uncertainty in ${\cal B}(\Lambda_c^+\to{p}K^-\pi^+)$, respectively. We also set an upper limit ${\cal B}(\bar{B}^0\to\Sigma_c(2520)^{0}\bar{p}\pi^+)<0.38\times10^{-4}$ at the 90% confidence level. In addition, we obtain a non-resonant branching fraction of $(6.4\pm0.4\pm\0.9\pm1.7)\times10^{-4}$, and a total branching fraction of $(11.2\pm0.5\pm1.4\pm2.9)\times10^{-4}$ for $\bar{B}^0\to\Lambda_c^{+}\bar{p}\pi^+\pi^-$.