抄録
The tracing-back method has been applied to the detection of showers which could be regarded as those produced by single nucleon-nucleon collisions in a stack of stripped emulsions exposed at the stratosphere. The method consists in tracing star-producing tracks back along their passage through successive emulsion strips and in finding primary interactions. It enabled us to detect the interactions without any bias irrespective of the number of accompanying evaporation prongs.
A shower of the type 1+5p detected by this method in a preliminary observation was analysed in terms of the single proton-proton collision. By the assumption of balance of transverse momenta for the charged outgoing particles alone, the incoming proton energy was estimated to be about 25 Gev and the inelasticity to be about 0.4. In this paper these results and another possible estimates has been presented together with a brief description of some features of the shower.
