Geiger-Mueller measurement

Counter, Geiger-Mueller (GM counter)—Highly sensitive, gas-filled radiation-measuring device to detect (count) individual photons or particulate radiation. 

Other techniques for the diffusion of gas through monolayers at the liquid interface have also been investigated (Blank, 1970). In these methods, the differential manometer system was used to measure the adsorption of gases such as C02 and 02 into aqueous solutions with and without the presence of monolayers. The Geiger-Mueller counter with a suitable sorbent and a radioactive tracer gas was used to measure the reduction of evolution of H2S and C02 from the surface solution when a monolayer was present. 

In a recent work, Aiba (A2) studied the flow currents in water, in a mixing vessel 14 in. in diameter, using an axially-mounted two-bladed flat paddle 4.7 in. in diameter. Measurements were made both without baffles and with four baffles %2 tank diameter wide. A sphere about 6 mm. in diameter was suspended by a flexible wire, and its displacement from the equilibrium (no-flow) position was measured. To get the horizontal displacement, cobalt-60 was embedded in the sphere, and a Geiger-Mueller counter approximately 10 mm. in diameter was immersed in the tank 2-5 cm. from the sphere. The vertical movement of the sphere was measured with a cathetometer, and its angular position observed by eye. From the known components of displacement and the assumed drag coefficient of the sphere, values of the radial, tangential, and vertical components of the flow around the sphere were calculated. 

E. Because of the weak beta radiation, tritium is NOT readily measured by the Geiger-Mueller counter used with most fielded radiac instruments and requires wipe testing swipes and a liquid scintillation detector to determine the level of contamination. 

Fig. 7. Comparison of Geiger-Mueller and photographic measurement of small angle scatter of heated gamma-alumina.

Fig. 19.1 Half a century ago, measurement of radioactive Iodine In the thyroid gland with a Geiger-Mueller counter placed at different points indicated...

A Geiger-Mueller tube is a gas-filled chamber used to measure alpha, beta, and gamma radiation. Radiation entering the mbe ionizes the gas and creates small currents that the instmment measures. 

The radioactive decay of an unstable nucleus is a random process. In any given interval of time, there is a well-defined probability that a given nucleus will decay. This probability is independent of time and is the same for aU nuclei of a given type, but is different for different isotopes. The number of nuclei decaying per unit time is the rate of nuclear decay (or activity), which can be measured using devices, such as the Geiger-Mueller counter (Figure 17.4). 

The area radiation monitoring system i II system consisting of two Rack Units possible) measuring channels. Each me of a model DAl-6 GM detector assembly 8 electronic channel. Units needing radiation level and a local alarm also indicator. All units have a range of mR/hour and use a geiger-mueller detec radiation. These units will continue 1000 R/hour fields. 

Monitoring occupational radiation exposure is a fundamental aspect of radiation protection. This can be done by measuring radiation fields with a common handheld instrument such as a Geiger-Mueller Counter and, if exposure conditions are predictable and relatively low (i.e., less than 10% of the regulatory limit), expected exposures can be calculated and documented. Alternately, regular radiation field survey measurements can be performed, and personnel dosimeters are issued to workers. 

The gold foil is counted with a calibrated Geiger-Mueller counter which has been calibrated previously by use of a standard pile of known flux. From this measurement, the thermal flux in which the phosphorus was irradiated can be determined. The phosphorus pellet is then counted with the end-window counter. As previously stated, the range of the beta particle determines the active weight which is counted. The counting rate is given by... 

The manganese foil discs and the sodium pellets do not require an absolute measurement of activity, since only their cadmium ratios are necessary for the experiment. The manganese will be counted with an end-window Geiger-Mueller counter, and the sodium with the Nal scintillation counter. 

The sulfur threshold detector is used to measure the integrated fast flux above 2.9 MeV. In Part B, the equation used to determine the fast flux is derived in conjunction with a phosphorus-pellet calibration of the Geiger-Mueller counter ... 

Geiger counter A radiation-detection and -measuring instrument. Consists of a gas-filled tube that discharges electrically when ionizing radiation passes through it. It was named for Hans Geiger and W. Mueller, who invented it in the 1920s. 

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