INVARIANT MASS DEPENDENCE OF PARTICLE CORRELATIONS IN PI(+)P AND K(+)P INTERACTIONS AT 250 GEV/C

We study two- and three-particle correlations as a function of invariant mass. Using data on pi+ p and K+p collisions at 250 GeV/c, we compare correlation functions and normalised factorial cumulants for various charge combinations. Strong positive correlations are observed only at small invariant masses. The normalised cumulants for ''exotic'' [(- -), (+ +)] and ''non-exotic'' pairs (+ -) and triplets decrease in power-like fashion with increasing invariant mass. The mass dependence is not incompatible with the power-law behaviour as expected in a Dual Mueller-Regge framework. Comparison with FRITIOF reveals strong disagreements, which are due to too large production rates of resonances, such as rho0 and eta, and the absence of a Bose-Einstein low-mass enhancement in JETSET.