The Franck-Hertz experiment re-considered

Using the Franck-Hertz Experiment To Illustrate Quantization: Energy States of the Neon Atom by Electron Impact

Laboratory exercises that illustrate quantum phenomena provide students with motivation for the study of quantum mechanics. That microscopic matter exists in quantized states can be demonstrated with modem versions of historic experiments: atomic line spectra (I), resonance potentials, and blackbody radiation. The resonance potentials of mercury were discovered by Franck and Hertz in 1914 (2). ...

The Franck-Hertz Experiment and the Ramsauer-Townsend Effect: Elastic and Inelastic Scattering of Electrons by Atoms

Franck and Hertz described the first observation of quantized excitation in 1914, one year after Bohr published his theory of the hydrogen atom with its concept of quantized energy states. They discovered that electrons moving through mercury vapor with an energy greater than or equal to a critical value near 4.9 eV can excite the 2536 Å line of the mercury spectrum. Electrons with less than th...

The Franck-Hertz Experiment and the Ramsauer-Townsend Effect: Elastic and Inelastic Scattering of Electrons by Atoms

Photoelectric Franck-Hertz experiment and its kinetic analysis by Monte Carlo simulation.

The electrical characteristics of a photoelectric Franck-Hertz cell are measured in argon gas over a wide range of pressure, covering conditions where elastic collisions play an important role, as well as conditions where ionization becomes significant. Photoelectron pulses are induced by the fourth harmonic UV light of a diode-pumped Nd:YAG laser. The electron kinetics, which is far more compl...

Early History of Physics with Accelerators

The early history of physics at accelerators is reviewed, with emphasis on three experiments which have had a profound influence on our view of the structure o f matter: The Franck and Hertz experiment demonstrating the mechanism of atomic spectra, the Cockcroft and Walton experiment opening practical ways of studying nuclear dipintegration, and the discovery of the A* isobar of the proton by F...