Geiger-Muller region

The Geiger-Muller detector is a radiation detector which operates in the G-M region. 

For metals which cannot be used in the form of a pinhole-free thin foil, an alternative method was developed (72). The electrode is made in the form of a tape. Adsorption of radioactive material occurs under potential control in a special cell with narrow slits, through which the tape passes under the Geiger-Muller counter. The slit through which the tape moves out of the adsorption region is sufficiently narrow to reduce the error introduced by the adhering layer of labeled solution to < 5%. 

Specimens were also collected away from the study area to be used as controls. Various portions of the animals were processed and counted. In a study of the uptake rate of DDT in Blarina, individuals were collected from the area, toe-clipped, and marked with a numbered aluminum leg band for identification. In addition, a 100- xCi piece of Ta wire was sealed in a nylon tube that was then placed under the skin in the intrascapular region with a modified hypodermic needle. As contrasted with other uses of this tagging method, it was necessary to anesthetize the shrew prior to injecting the wire. The Ta tag was intended to facilitate locating the animals with a Geiger-Muller (GM) field survey meter for periodic collection. The investigators commented that the use of this tag to facilitate recapture was almost totally unsuccessful, since the animals were apprently too far below the surface to locate with the survey meter. 

Figure 4 Gas-amplification characteristics of gas-filled detectors. Most flow counters for WDXRF are operated in the changeover region from proportional to Geiger-Muller.

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