Geiger counter

1935 Geiger counter

The book of science

Tom Sharp

John Sealy Townsend, Hans Geiger, Walther Müller physics

Geiger counter

Townsend discharge

Maligning atoms

John Sealy Townsend became a research student at Cambridge at the same time as Ernest Rutherford, and Hans Geiger studied under Ernest Rutherford at the University of Manchester. Ernest Rutherford distinguished alpha and beta particles. Alpha decay is the emission of a particle containing two protons and two neutrons; beta decay is the emisson of an electron or positron. Gamma radiation is the emision of high-energy photons.

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