This diagram shows the s-channel single-top quark production mechanism sought in this analysis, which selects signal events in which the lepton is not identified. In collisions of high-energy beams, new, heavy particles are usually produced in pairs: a matching antiparticle for every particle. That’s the case for the bottom quark and the top quark, both discovered at Fermilab. But every now and then, the weak force is responsible for the collision, and so particles can be transmuted from one kind…