Clustering in four-dimensional relative-velocity space and invariant distributions of hadron jets

A relativistically invariant method is discussed for separation of hadron jets, based on minimization of the sum of the squares of the relative 4-dimensional velocities. This method has been applied to analysis of the properties of jets in π-p and π-C interactions at 40 GeV/c and in pp collisions at P = 205 GeV/c. The scaling properties of the invariant function W(b/sub α//sub k/, b/sub β//sub k/, b/sub α//sub β/,...) are investigated experimentally in 4-dimensional relative-velocity space. It is shown that distributions of pions in jets in the variable x/sub k/ = b/sub α//sub k//b/sub α//sub β/, b/sub β//sub k//b/sub α//sub β/,..., as in the variable b/sub k/ which was studied previously, have a universal nature in various types of collisions in the momentum range 40--205 GeV/c