The Modern Emulsion Technique and a Research for Cosmic Rays

Abstract

An Emulsion Cloud Chamber has been widely used to study high energy cosmic rays. Recently, this detector has been extensively improved and developed to a Micro Segment Chamber (MSC). The MSC basically consists of a stack of thin and low-background emulsion film which can be used for high-speed image processing. A sophisticated image processing technique makes it possible to analyze a lot of emulsion films of a kiloton scale. Using this MSC, we have succeeded to detect v_τ events, and are going to start the OPERA experiment at CERN to search for v_μ-v_τ oscillation phenomena. In this article, we briefly introduce the performance and the balloon-borne MSC designed for observing cosmic ray electrons. We also discuss the possibility of searching for WIMPs using super-fine grain emulsion films.