“…Emulsion chambers, i.e. stacks of nuclear emulsions when used in cosmicray experiments, are frequently equipped with additional large-area X-ray films [61][62][63]. The main differences of the X-ray films from nuclear emulsions are the low grain size from 50 nm to 200 nm (0.05-0.2 microns) at a thickness of 7-20 microns [64].…”