Strange quarks are naturally radioactive and decay by weak interactions into lighter quarks on a timescale that is extremely long compared with the nuclear-collision times. This makes it relatively easy to detect strange particles through the tracks left by their decay products. Consider as an example the decay of a negatively charged Ξ Ξ baryon (green in figure, dss), into a negative pion (u d) and a neutral Λ Λ (uds) baryon. Subsequently, the Λ Λ decays into a proton and another negative pion. In general this is the signature of the decay of a Ξ Ξ . Although the negative Ω Ω (sss) baryon has a similar final state decay topology, it can be clearly distinguished from the Ξ Ξ because its decay products are different.