Search for the Weak Decay of an H Dibaryon

TL;DR

This paper reports a search for a hypothetical H dibaryon particle decaying into Lambda and neutron or Sigma0 and neutron, setting upper limits on its production based on candidate events.

Contribution

First experimental search for the weak decay of an H dibaryon, providing upper limits on its production cross section near 2.15 GeV/c^2.

Findings

Two candidate events observed

Upper limit on H production cross section

Normalized to Lambda production cross section

Abstract

We have searched for a neutral $H$ dibaryon decaying via $H\to\Lambda n$ and $H\to\Sigma^0 n$. Our search has yielded two candidate events from which we set an upper limit on the $H$ production cross section. Normalizing to the inclusive $\Lambda$ production cross section, we find $(d\sigma_H/d\Omega) / (d\sigma_\Lambda/d\Omega) < 6.3\times 10^{-6}$ at 90% C.L., for an $H$ of mass $\approx$ 2.15 GeV/$c^2$.