Measurement of the Leading Charged Particle Charge Ratios in High Transverse Momentum Proton-Proton and Pion - Collisions.

A fixed target experiment performed at Fermilab used double-arm calorimeter triggers to study high p(,T) clusters of secondary particles produced by +400 GeV/c (p) and -200 GeV/c ((pi)) beam particles on a 45 cm liquid hydrogen target. A magnet downstream of the target produced 0.1 GeV/c deflections for charged particle secondaries. A study has been made of the leading charged particles in the calorimeter trigger regions. We find that the ratio (+/-) of the leading charged particles is consistent with soft gluon structure functions for both the proton and the pion.