Phototriton Cross Section ofLi6

Abstract

The phototriton cross section of ${\mathrm{Li}}^{6}$ has been measured between 24- and 35-MeV photon energy. This work complements an earlier experiment which established the production of the ${\mathrm{Li}}^{6}(\ensuremath{\gamma},t)$ reaction by giant-resonance photons and measured the cross section between 19 and 24 MeV. The phototriton cross section of ${\mathrm{Li}}^{6}$ falls monotonically from 0.46\ifmmode\pm\else\textpm\fi{}0.24 mb at 19 MeV to 0.11\ifmmode\pm\else\textpm\fi{}0.06 mb at 35 MeV. The integrated ($\ensuremath{\gamma},t$) cross section over this energy interval is 4.9\ifmmode\pm\else\textpm\fi{}2.5 MeV mb. The measured bremsstrahlung-weighted cross section is 0.18\ifmmode\pm\else\textpm\fi{}0.09 mb. Implications concerning the nuclear size are discussed.