Determination of parameters relevant to alpha spectrometry when employing source coating

Preparation and characterization of electrodeposited layers as alpha sources for alpha-particle spectrometry

“…The contamination raises the background or products new peaks which may overlap with significant peaks. Generally, three techniques such as the operation of the spectrometer with an air barrier [105,145], the source covering with a thin even foil [141,146], and the application of a voltage between source and the detector where the source is negatively biased by a few volts [144], have been used to avoid the recoil contamination in alpha spectrometry. The correlation of the recoil with the chemical and crystal structures of the electrodeposited alpha-source has not been studied.…”

Alpha-particle spectrometry for the determination of alpha emitting isotopes in nuclear, environmental and biological samples: past, present and future

“…Coating with a thin lm of Mylar of 0.25 mg cm À2 (metalized lm made of polyester or polycarbonate coated with aluminium) was shown to alleviate the contamination problem with recoil nuclei, and also in the case of 210 Po, with no signicant change in the FWHM of the alpha spectra. 50 Disposable thin collodion (cellulose nitrate) lms were used as catchers to stop the recoil contamination of the detector, 51 for sources prepared by electrodeposition as well as by co-precipitation. A thin formvar lm (polyvinyl formaldehyde) was used as a stopper foil in the determination of 226 Ra in water samples by a-spectrometry.…”

Collection and behaviour of radon progenies on thin Mylar foils

“…For samples containing nuclides such as 229 Th, 228 Th or 226 Ra, which produce shortlived alpha-particle-emitting daughters within their decay chains, recoil contamination of the detector is a well-known problem (Sill and Olson, 1970). This effect can be reduced by slightly increasing the pressure in the measurement chamber and applying a negative potential to the alpha source (Sill and Olson, 1970) or by using thin foils that do not significantly influence the energy resolution of a measurement to physically protect the detector (Vainblat et al, 2004). Commercially available biaxially-oriented polyethylene terephthalate (Mylar) foils are often used for this purpose.…”