title: Uniformity measurement of wide area reference sources for beta emitters.
abstract: When conducting uniformity measurements of a wide area reference source with a detector having a window of a size similar to that of a gridded individual portion area on the source, it is important to carefully consider neighbor effects on measuring emission rates of the individual target portion resulting from the gap between the source and detector window. Optimization of the uniformity measurement conditions was studied for beta-emitting wide area reference sources in this study. A measurement system consisting of a PR-gas (Ar: 90%+CH4: 10%) flow type windowed proportional counter and a motorized XY stage was installed. This system is adapted to the uniformity measurement of two different types of (36)Cl sources made by different manufacturers. Uniformity measurement of a 100mm×100mm source divided into 16 portions of 6.25cm(2) (25mm squared) each could be conducted using our system under the present conditions with a neighbor effect of around 15% or less. The measurement results by use of this system were also compared with those using the imaging plate technique.
authors.affiliation: Japan Radioisotope Association, 2-28-45, Hon-komagome, Bunkyo, Tokyo 113-8941, Japan. Electronic address: ohshiro-masahiro@jrias.or.jp.
authors.forename: Masahiro
authors.initials: M
authors.lastname: Ohshiro
authors.affiliation: Japan Radioisotope Association, 2-28-45, Hon-komagome, Bunkyo, Tokyo 113-8941, Japan.
authors.forename: Takuya
authors.initials: T
authors.lastname: Shiina
authors.affiliation: Japan Radioisotope Association, 2-28-45, Hon-komagome, Bunkyo, Tokyo 113-8941, Japan.
authors.forename: Takahiro
authors.initials: T
authors.lastname: Yamada
keywords: Extended sources; ISO 8769; Instrument efficiency; Reference source; Surface contamination