Scaling and Factorization inK++p→π−+Anything

Abstract

We report, with good statistics, the $\pi$ momentum distributions from the reaction $K^{+}+p\to {\pi }^{-}+$ anything at 11.8 $\frac{\mathrm{GeV}}{c}$. We compare the shape of the distribution in longitudinal momentum of the ${\pi }^{-}$ with that of ${\pi }^{-}$ mesons produced in the reaction ${\pi }^{-}+p\to {\pi }^{-}+$ anything at 25 $\frac{\mathrm{GeV}}{c}$ and ${\pi }^{+}+p\to {\pi }^{-}+$ anything at 18.5 $\frac{\mathrm{GeV}}{c}$ in terms of the scaling variable $x=\frac{2p_L}{\sqrt{s}}$. The backward distributions are found to be independent of the nature of the projectile. The forward distributions are different in shape from the backward, but are remarkably similar for $K^{+}p$ and ${\pi }^{+}p$ interactions. The distribution in longitudinal momentum in the center-of-mass system is not independent of the value of the transverse momentum.