Abstract

${\ensuremath{\pi}}^{+}p$ and $\mathrm{pp}$ interactions at 100 GeV/c are studied in the National Accelerator Laboratory 30-in. bubble chamber with a tagged beam. Charged multiplicities in ${\ensuremath{\pi}}^{+}p$ and $\mathrm{pp}$ interactions are compared. The average inelastic multiplicity of ${\ensuremath{\pi}}^{+}p$ interactions is higher than for $\mathrm{pp}$ interactions (6.80 \ifmmode\pm\else\textpm\fi{} 0.14 versus 6.49 \ifmmode\pm\else\textpm\fi{} 0.10). However, negative particle multiplicities for events with more than six charged particles follow Poisson statistics with similar means, 2.56 \ifmmode\pm\else\textpm\fi{} 0.09 and 2.61 \ifmmode\pm\else\textpm\fi{} 0.08, for ${\ensuremath{\pi}}^{+}p$ and $\mathrm{pp}$ interactions.