Isotopenbestimmung mit der Goldabsorptionsmethode

Abstract

Es wird eine schnelle und einfache Methode beschrieben die die Identifizierung yon Beta-strahlenden radioaktiven Isotopen ermOglicht. Die geringste AktivitXt die man hOCk mit dieser Methode identifizieren kaml betr~gt 50 mikro-mikro-Curie. Die Methode beruht auf den empirischen Belunden, dab die Absorption yon Beta-Spektren in Materialien yon hoher Atomnummer exponentiaI verl~uft und dab die Goldabsorptionskoeffizienten umgekehrt proportional tier 3/2-ten Potenz tier maximalen Energie der Beta-Spektra sind. Der Goldabsorptionskoeffizient kann somit, neben Halbwertszeit und maximaler Energie, als ein weiteres Kennzeichen yon Beta-Strahlern betrachtet werden, Die Anwendung der Methode zur qualitativen und quantitativen Analyse von Isotopengemischen wird beschrieben.

Simple Absolute Measurement Technique for Beta Radioactivity. Application to Naturally Radioactive Rubidium

“…Furnished by National Bureau of Standards. 6 Furnished by Oak Ridge National Laboratory. Equation 2 is simple enough to allow use in high school laboratory experiments.…”

“…The absorption coefficient, l/ , has been found (6,20,25) to depend on the maximum energy of the beta spectrum, E, in the following way: X(mg./sq. cm.)…”

“…The fact that absorption curves which are nearly exponential in nature can be obtained under certain conditions has long been known (6,10,18,25,27). As has been shown (18,SO) if the absorption of the radiation is exponential the total self-absorption in an ordinary solid or liquid sample, which has finite thickness and therefore can be readily made and handled, can be calculated easily and the relation between the absolute disintegration rate and the observed count rate obtained.…”

Absorption and Luminescence in Impurity-activated Alkali Halides.

“…In the original work, the Gottingen group measured the absorption spectra of various alkali halides activated by small amounts of thallium (25,36,40), copper (23,135), silver (40,135), and lead (36). They studied the variation of the absorption with concentration of impurity (23,67,68) and found that, at least for low concentrations, the intensity of absorption is directly proportional to the concentration of the impurity.…”

Fluorescence of Thallium-Activated Halide Phosphors

“…The absorption spectra of Tl-activated alkali halide phosphors (1,2) have been studied extensively and their excitation and emission spectra (3,4) have received some attention. 1 In addition an attempt has been made to calculate from first principles the absorption and emission spectrum of Tl-aetivated KC1 (5) and to correlate this ~dth experimental data, including data on thermoluminescence.…”