250-GeV/cπ−pmultiplicity distributions and the two-component model

The charged-particle multiplicity distribution from 250-GeV/c ${\pi }^{-}p$ interactions in the Fermilab 15-ft bubble chamber is presented. The corrections to the raw data are described. Fits to these data along with other high-energy bubble-chamber data show that cluster models with two components—a low-multiplicity, diffractive component and a high-multiplicity, nondiffractive component—describe the data fairly well. The charged multiplicity of each cluster is found to be ∼2, while the number of clusters for each component grows linearly with $\ln \mathrm{}\left(s\right)\mathrm{}$. The multiplicity moments are consistent with other experiments. We find $〈n_c〉=8.427\mathrm{}\pm 0.059$, $f_2^{\mathrm{cc}}=8.66\mathrm{}\pm 0.11$, $\frac{〈n_c〉}{D}=2.038\mathrm{}\pm 0.023$. The total inelastic cross section is ${\sigma }_I=21.42\mathrm{}\pm 0.50$ mb.