Electron Background in Imported G5 Emulsions

Abstract

Ilford G5 nuclear emulsions have been received by this department at regular fortnightly intervals during the last six months. They are sent by air mail and reach this laboratory approximately two weeks after the date of manufacture in England and are developed soon after arrival. Heavy electron backgrounds were observed in four batches of plates out of 12 successive fortnightly shipments. Possible causes of these variations have been investigated.