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A drift chamber uses the drift times of ionization Electrons in a gas to infer positions along charged particle tracks. In a known magnetic field, track reconstruction can estimate momentum and the sign of electric charge.

A multiwire proportional chamber is a proportional counter: parallel anode wires between cathodes in a gas. Charged particle ionization frees Electrons; an electric field drives them toward wires, triggering an electron avalanche read by electronic amplifiers.^[ref]

Georges Charpak's electronic readout avoided film scanning and full spark chamber discharge.^[ref]

Opposite polarities identify the avalanche wire. Positive ion motion dominates integrated signal; detection precedes complete collection. Calibrated Electron travel times enable drift chambers.^[ref]

A W boson decay can leave one visible charged lepton and a large missing transverse momentum; a Z boson decay can instead supply two visible leptons whose four-momenta determine an invariant mass. The two signatures answer the same existence question with different missing information. The electroweak unification history recognized by the 1979 Nobel Prize in Physics predates these 1983 observations: the W boson and Z boson were predictions to test, rather than particles first proposed in 1983.

The Super Proton-Antiproton Synchrotron stored counterrotating proton and antiproton beams; stochastic cooling made accumulation of the scarce antiprotons practical. Carlo Rubbia's 1984 lecture describes track reconstruction in a large drift chamber inside a magnetic field, surrounded by segmented particle calorimeters. Their nearly complete angular coverage allowed an imbalance test for unobserved neutrinos.^[ref]