A new apparatus for track-analysis in nuclear track emulsion based on a CCD-camera device

Abstract

A CCD camera-based, image-analyzing system for automatic evaluation of nuclear track emulsion chambers is presented. The stage of a normal microscope moves using three remote controlled stepping motors with a step size of 0.25 microm. A CCD-camera is mounted on top of the microscope in order to register the nuclear emulsion. The camera has a resolution capable of differentiating single emulsion-grains (0.6 microm). The camera picture is transformed from analogue to digital signals and stored by a frame grabber. Some background-picture elements can be eliminated by applying cuts on grey levels. The central computer processes the picture, correlates the single picture points, the coordinates and the grey-levels, such that in the end one has a unique assignment of each picture point to an address on the hard disk for a given plate. After repetition of this procedure for several plates by means of an appropriate software (for instance our vertex program [1]), the coordinates of the points are combined to tracks, and a variety of distributions like pseudorapidity-distributions can be calculated and presented on the terminal.