Ring events in high-energy hadron processes
Dremin I. M. , Orlov A. M. , Tret'yakova M. I.
Some of the events observed in 400-GeV proton-nucleon interactions have dense clusters of particles on the pseudorapidity scale, corresponding to a ring-shaped structure for the target diagram. Events of this type have been singled out and studied. It is found that such clusters are emitted preferentially at cm. angles of about 55°, 90°, and 125°.