A β-Ray Source Preparation Method by the Use of Backing Film Coated with Aluminum

Abstract

The preparation method for the source of 4πβ-counting which had less self-absorption and better uniformity was studied.
The procedures of the preparation were as follows. The solution of radioactive nuclide was dropped upon the source backing film coated with aluminum and dried up under an infrared lamp. Then the source material dried up on the film was again dissolved by adding a small amount of distilled water and finally dried up in an ammoniac atmosphere.
By this method, the source material was distributed uniformly by the presence of fine particles of aluminum compound which were produced in the solution of radioactive nuclide.
The self-absorption for β-rays of the sources of ⁴⁶Sc, ⁶⁰Co, and ²⁰³Hg was measured by means of 4πβ-γ coincidence method and the uniformity of them was observed auto-radiographically and microphotographically. The self absoption in this method was little less than that in colloidal silica treatment or precipitation method.