QUALITATIVE AND QUANTITATIVE GAMMA ANALYSIS OF LOWER ACTIVITIES BY GREY WEDGE METHOD

Journal Article · Fri Sep 01 04:00:00 EDT 1961 · Telefunken Ztg.

OSTI ID:4801352

Tzschaschel, R

The Telefunken Pulse Height Analyzer MS Str 531 is an equipment combining a customary single-channel system with a grey-wedge analyzer (produced commercially for the first time). The grey-wedge method supplies results quite comparable with those of four-channel spectrometry, which is described. Comparative measurements between the single-channel and the grey-wedge method are discussed, The samples measured are total solids from rain water and some soil samples from the vicinity of the nuclear research center at Julich. All samples had a very low activ ity. Particularly striking are the great differences in the measuring time in the two methods and the much higher content of information provided by the grey-wedge spectra, which can even be recognized at the shortest exposure time of half an hour. The latter is quite understandable because in principle the grey-wedge spectrum is a multichannel spectrum produced with optical means. A table gives a summary of the fallout nuclides ascertained in the grey-wedge spectrograms. The evaluation of the greywedge spectrograms, i.e., the calibration of the energy sxis and a suitable method of printing the spectrum, is described. A family of calibration curves that were measured using various samples is shown. If grey-wedge spectra are to be printed in a scientific publication it is recommended, for reasons of clarity, to print the energy scales with arrows pointing to the nuclides determined. The so-called equi-density method'' permits representing the grey-wedge spectrum as a kind of written singlechannel or multi-channel spectrum. The calibration of the activity axis of a grey-wedge spectrum is described. Calibration was effected with the iodine isotopes I/sup 131/ of which various samples at different activities were available. Grey-wedge recordings were made and the height of the gamma lines measured. In the semi-logarithmic scale the results obtained in this manner show strict linearity between the activity and the height of the gamma lines. As regards estimating the accuracy of energy and activity calibrations, the following should be mentioned in conclusion: in principle handling the grey-wedge spectrometer necessitates highly accurate photography, to which the physicist is accustomed from spectrum optics. If this accuracy is given, then the energies of unknown nuclides and the activities of definite nuclides can be ascertained with an accuracy of approximately 3 to 5%. (auth)

• Research Organization: Originating Research Org. not identified
• NSA Number: NSA-16-027338
• OSTI ID: 4801352
• Journal Information: Telefunken Ztg., Journal Name: Telefunken Ztg. Vol. Vol: 34: No. 133
• Country of Publication: Country unknown/Code not available
• Language: German

Related Subjects

CONTAMINATION
ENGINEERING AND EQUIPMENT
GAMMA RADIATION
IODINE 131
LABORATORY EQUIPMENT
MEASURED VALUES
OPTICAL SYSTEMS
PHOTOGRAPHY
PULSE ANALYZERS
RADIOACTIVITY
RAIN
RECORDING SYSTEMS
SAMPLING
SOILS
SPECTRA
SPECTROMETERS
WATER