A Search for the Transmutation Products of Gamma-Meson Reactions Induced by 100-Mev X-Rays

Irradiation with 100 Mev x-rays has been found to produce ${\mathrm{Zn}}^{63}$ from copper and ${\mathrm{Mg}}^{27}$ from aluminum. Experiments involving variations in beam energy and target thickness have shown that these isotopes result from secondary reactions caused by photo-neutrons and photo-protons from the target materials rather than from any primary, x-ray induced processes. No evidence for gamma-meson reactions has been obtained. A search for the transmutation products of gamma-meson reactions is shown to compare favorably in sensitivity with cloud-chamber methods for the detection of meson production, provided mesons are produced singly.