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an instrument or apparatus by which numerical value is computed; in radiology, a device for enumerating ionizing events.
Coulter counter an automated instrument for performing blood counts, based on the principle that cells are poor electrical conductors compared with saline solution.
Geiger counter (Geiger-Müller counter) a radiation counter using a gas-filled tube that indicates the presence of ionizing particles. It is very sensitive to β particles but relatively insensitive to γ and x-rays.
scintillation counter a device for detecting ionization events, permitting determination of the concentration of radioisotopes in the body or other substance.
Gei·ger-Mül·ler count·er(gī'gĕr mūl'ĕr),
an instrument for measuring radioactivity by counting the emission of radioactive particles; it consists of a metallic cylinder, negatively charged, in a tube containing a fine, positively charged wire at its center; radiations produce ionization of the gas molecules between the cylinder and the wire and result in an electrical discharge independent of the energy of the impinging particle or ray.
Geiger,Hans, German physicist, 1882-1945.
Geiger-Müller counter - an instrument for measuring radioactivity by counting the emission of radioactive particles.
Müller,Walther, 20th century German physicist.
Geiger-Müller counter - see under Geiger