A cobalt 58 ‘slow positron generator’

Abstract

A 58Co source is combined with a tungsten (110) moderator in reflection geometry, in a 12.7 mm diameter × 12.7 mm long capsule. We refer to this device as a slow positron generator or SPG. Rates of ∼5 × 10 6 slow e +/s are expected from 1 Ci sources. The capsules can be reused, and are sent back to the point of manufacture for refurbishing, and replacement of the cobalt source. A comparison is made between 58Co and 22Na. To facilitate a number of positron researchers at various institutions, positron resources incorporated was formed. Recent work on these sources has been done under a CRADA between positron resources, Idaho National Engineering Laboratory and the DOE.