Automatic scanning for nuclear emulsion

Automatic scanning systems have been recently developed for application in neutrino experiments exploiting nuclear emulsion detectors of particle tracks. These systems speed up substantially the analysis of events in emulsion, allowing the realisation of experiments with unprecedented statistics. The pioneering work on automatic scanning has been done by the University of Nagoya (Japan). The so called new track selector has a very good reproducibility in position (∼1 μm) and angle (∼3 mrad), with the possibility to reconstruct, in about 3 s, all the tracks in a view of 150×150 μm2 and 1 mm of thickness. A new system (ultratrack selector), with speed higher by one order of magnitude, has started to be in operation. R&D programs are going on in Nagoya and in other laboratories for new systems. The scanning speed in nuclear emulsion be further increased by an order of magnitude. The recent progress in the technology of digital signal processing and of image acquisition systems (CCDs and fast frame grabbers) allows the realisation of systems with high performance. teresting applications of the technique in other fields (e.g. in biophysics) have recently been envisaged.