The development of a super-fine-grained nuclear emulsion

Abstract

A nuclear emulsion with micronized crystals is required for the tracking detection of submicron ionizing particles, which are one of the targets of dark-matter detection and other techniques. We found that a new production method, called the PVA-gelatin mixing method (PGMM), could effectively control crystal size from 20 nm to 50 nm.We called the two types of emulsion produced with the newmethod the nano imaging tracker and the ultra-nano imaging tracker. Their composition and spatial resolution were measured, and the results indicate that these emulsions detect extremely short tracks.