Tau (particle) Tau (particle) The tau (τ), also called the tau lepton, tau particle, or tauon, is an elementary particle similar to the electron, with negative electric charge and a spin of. Together with the electron, the muon, and the three neutrinos, it is a lepton. Like all elementary particles with half-integer spin, the tau has a corresponding antiparticle of opposite charge but equal mass and spin, which in the tau's case is the antitau (also called the "positive tau"). Tau particles are denoted by and the antitau by . Tau leptons have a lifetime of and a mass of (compared to
Craig (given name) Craig (given name) Craig is a Scottish, Irish & Welsh masculine given name, all variations derive from the same Celtic branch. The name has two origins. In some cases it can originate from a nickname, derived from the Scottish Gaelic word "creag", meaning "rock," similar to Peter. In other cases, the given name originates from the Scottish surname "Craig", which is also derived from the same Scottish Gaelic word. Cognate forms of "creag" include the Irish "creig", Manx "creg", and Welsh "craig". The English word "crag" also shares an origin with these Celtic words. The given name "Craig" is popular