Production ofπ+Mesons at 0° by 335-Mev Protons on Deuterium and Complex Nuclei

The relative yield of ${\pi }^{+}$ mesons has been determined for 335-Mev protons on several elements. Specifically, the relative differential cross section, $\frac{d^2\sigma }{\mathrm{dEd}\Omega }$, was measured at 0°±4° in the reaction $p+A\to {\pi }^{+}+A^{\prime }$ for D, ${\mathrm{Be}}^9$, ${\mathrm{B}}^{10}$, B (natural), C, Al, Cu, Fe, Ag, and Pb. The ${\pi }^{+}$-meson energies ranged from 34 to 147 Mev. They were counted electronically from signals generated in a trans-stilbene crystal telescope. Identification of the ${\pi }^{+}$ meson depended upon a coincidence in the first two crystals plus the ${\pi }^{+}-{\mu }^{+}$ decay in the third crystal of the telescope.