How Does a Geiger Counter Work?
A “Geiger counter” is named for the Geiger-Mueller tube, which is the core component of the device. This tube contains a thin metal wire through its center, the space in between sealed and filled with gas. The wire carries a charge of ca. +1000 volts relative to the tube. An nuclear particle (ion or electron) penetrating the tube (or an electron knocked out of the wall by X-rays or gamma rays) tears electrons off atoms in the gas, and because of the high positive voltage of the central wire, those electrons are then attracted to it. In the process they gain energy, colliding with atoms and releasing more electrons, until the process cascades into a “waterfall” producing an easily detectable pulse of current. The instrument is called a “counter” because every particle passing through it produces an identical pulse, allowing particles to be counted electronically.
The Geiger counter, named after one of the men who invented it, is a device used to find out how much radioactivity is present in a substance or an area. It works somewhat the way a neon light works. In a neon light, an electrical current excites gas molecules inside the glass tube, causing them to glow. Like the neon light, a G
A “Geiger counter” is named for the Geiger-Mueller tube, which is the core component of the device. This tube contains a thin metal wire through its center, the space in between sealed and filled with gas. The wire carries a charge of ca. +500 volts relative to the tube. An nuclear particle or gamma quant (ion or electron) penetrating the tube (or an electron knocked out of the wall by X-rays or gamma rays) tears electrons off atoms in the gas, and because of the high positive voltage of the central wire, those electrons are then attracted to it. In the process they gain energy, colliding with atoms and releasing more electrons, until the process cascades into a “waterfall” producing an easily detectable pulse of current.
