Si28−30(n,xγ)Reactions for5.3<~En<~9.0MeV

Interactions of neutrons with silicon have been studied by measuring $\gamma$-ray production cross sections. For incident mean neutron energies $E_n=5.35,5.85,6.4,6.9,7.45,7.95,8.5, \mathrm{and} 9.0$ MeV, spectra were obtained for a natural silicon sample. The $\gamma$ rays were detected using a coaxial Ge(Li) detector of 30-${\mathrm{cm}}^3$ active volume. Data were obtained for $\gamma$-ray scattering angles of 55 and 90° for all $E_n$, of 35° for $E_n=7.45\mathrm{} \mathrm{and} 8.5$ MeV, and of 75° for $E_n=6.4\mathrm{} \mathrm{and} 7.45$ MeV. Time of flight was used with the detector to discriminate against pulses due to neutrons and background radiation. Data were also obtained at $E_n=5.9\mathrm{}$ MeV, ${\theta }_{\gamma }={55}^{\circ }$ for a sample of ${}_{}{}^{29}{}_{}{}^{}\mathrm{SiO}_2^{}{}_{}{}^{}$ enriched to 95% in ${}_{}{}^{29}{}_{}{}^{}\mathrm{Si}$, and for a similarly enriched sample of ${}_{}{}^{30}{}_{}{}^{}\mathrm{SiO}_2^{}{}_{}{}^{}$. These data have been studied to obtain absolute cross sections for production of $\gamma$ rays for the incident neutron energies quoted above. The cross sections have been compared, where possible, with previously measured values; agreement was fair.