In general, the geiger plateau is the voltage range in which the Geiger-Müller counter operates. Depending on the characteristics of the specific counter (manufacturer, size, gas type etc.) the exact voltage range may vary. In this region the potential difference in the counter is strong enough to ionize all the gas inside the tube, upon triggering by the incoming ionizing radiation (alpha , beta or gamma radiation). Below the plateau there are almost no counts due to high recombination rate. Higher voltages cause a phenomenon called quenching in which the positively charged ions are drawn to the cathode thus creating a continuous electric pulse in the counter. Ionization is the physical process of converting an atom or molecule into an ion by changing the difference between the number of protons and electrons. ... An alpha particle is deflected by a magnetic field Alpha particles or alpha rays are a form of particle radiation which are highly ionizing and have low penetration. ... Beta particles are high-energy electrons emitted by certain types of radioactive nuclei such as potassium-40. ... This article is about electromagnetic radiation. ...

The plateau, on the other hand, is the region in which approximately all of the ionizations are read and counted. The plateau has a slight incline caused by increased sensitivity to low energy radiation, due to the increased voltage on the device. Normally when a particle enteres the tube and ionizes one of the gas atoms, complete ionization of the gas occures. Once a low energy particle enteres the counter, it is possible that the kinetic energy in addition to the potential energy of the voltage are unsufficiant for the additional ionization to occure and thus the ion recombines. On higher voltages, the threshold for the minimum radiation level drops, thus, the counter's sensitivity rises. The kinetic energy of an object is the extra energy which it possesses due to its motion. ...