Proton scattering from an excited nucleus(18Fm,Jπ=5+,Ex=1.1 MeV) using a γ-ray-tagged secondary isomeric nuclear beam

We have used γ-ray tagging to identify a secondary isomeric beam of the short-lived, high-spin isomer ${}_{}{}^{18}{}_{}{}^{}\mathrm{F}_{}^{\mathit{m}}{}_{}{}^{}$ (${\mathit{E}}_{\mathit{x}}$=1.1 MeV, ${\mathit{J}}^{\mathrm{\pi }}$=$5^{+}$) produced at the K1200 cyclotron at the National Superconducting Cyclotron Laboratory. Elastic scattering of p${+}^{18}$ ${\mathrm{F}}^{\mathit{m}}$ at ${\mathit{E}}_{\mathrm{c}.\mathrm{m}.\mathrm{}}$≊20 MeV was observed using the characteristic γ decays of ${}_{}{}^{18}{}_{}{}^{}\mathrm{F}_{}^{\mathit{m}}{}_{}{}^{}$ (${\mathit{T}}_{1/2}$=163 ns) to identify the state of the projectile after the scattering, thus minimizing the probability of excitation of the beam and, hence, nonelastic scattering.