About Hans Geiger
Johannes Wilhelm "Hans" Geiger was a German experimental physicist. He is known as the inventor of the Geiger counter, a device used to detect ionizing radiation, and for carrying out the Rutherford scattering experiments, which led to the discovery of the atomic nucleus. He also performed the Bothe–Geiger coincidence experiment, which confirmed the conservation of energy in light-particle interactions. In 1911, Geiger and John Mitchell Nuttall discovered the Geiger–Nuttall law (or rule) and performed experiments that led to Rutherford's atomic model. In 1928, Geiger and his student, Walther Müller, created the Geiger–Müller tube. Geiger was awarded the Hughes Medal in 1929 for this work. In 1929, Geiger was appointed Professor of Physics and Director of Research at the University of Tübingen, where he made his first observations of a cosmic ray shower.
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