Search for the decay mode $B^0\rightarrow p p \bar{p} \bar{p}$

TL;DR

This paper reports a search for the rare four-body decay of the B0 meson into two protons and two antiprotons, using data from the BaBar experiment, resulting in a measured branching fraction with moderate significance.

Contribution

First search for the decay mode B0→ppp̄p̄ using a large data sample, providing an upper limit on its branching fraction.

Findings

Measured branching fraction: (1.1 ± 0.5 ± 0.2) × 10^{-7}

Signal significance: 2.9 standard deviations

Upper limit on branching fraction: 2.0 × 10^{-7} at 90% CL

Abstract

A search is presented for the four-body decay $B^0\rightarrow p p \bar{p} \bar{p}$ in a sample of $471$ million $B\bar{B}$ pairs collected with the BaBar detector, operated at the SLAC PEP-II asymmetric-energy $e^+e^-$ collider. The center-of-mass energy is $10.58$ GeV. From a fit to the distribution of the energy-substituted mass $m_{\mathrm{ES}}$, the result $\mathcal{B}(B^0\rightarrow p p \bar{p} \bar{p})=(1.1 \pm 0.5 \pm 0.2) \times 10^{-7}$ is extracted, where the first uncertainty is statistical and the second is systematic. The significance of the signal is $2.9$ standard deviations. The upper limit on the branching fraction is determined to be $2.0 \times 10^{-7}$ at $90\%$ confidence level.