Particle Production at High Transverse Momentum

We have measured $\frac{d^2\sigma }{d\Omega \mathrm{dp}}$, the differential cross section for the production of ${\pi }^{\pm }$ mesons, at high $P_{\perp }$, in 12.5-GeV/c proton-proton collisions. We covered the range $P_{\perp }^{}{}_{}{}^2=1.0-4.0\mathrm{}$ ${(\mathrm{G}\mathrm{e}\mathrm{V}/\mathit{c})}^2$ and the cross section appears to break at about 1.5 ${(\mathrm{G}\mathrm{e}\mathrm{V}/\mathit{c})}^2$. Thus, $\frac{d^2\sigma }{d\Omega \mathrm{dp}}$ appears to be the sum of two Gaussians in $P_{\perp }$.