Search for a Stable Six-Quark State at BABAR

Abstract

International audienceRecent investigations have suggested that the six-quark combination uuddss could be a deeply bound state (S) that has eluded detection so far, and a potential dark matter candidate. We report the first search for a stable, doubly strange six-quark state in ϒ→SΛ¯Λ¯ decays based on a sample of 90×106ϒ(2S) and 110×106ϒ(3S) decays collected by the BABAR experiment. No signal is observed, and 90% confidence level limits on the combined ϒ(2S,3S)→SΛ¯Λ¯ branching fraction in the range (1.2–1.4)×10-7 are derived for mS<2.05  GeV. These bounds set stringent limits on the existence of such exotic particles