Fission Yields of Several Iodine Isotopes and Half-Life and Fission Yield ofTe135

Abstract

Measurements have been made of the independent fission yields of several iodine isotopes in thermal-neutron-induced fission of $^{235}\mathrm{U}$. These yields were obtained by isolation of iodine-fission products at early times after fission by a new, fast radiochemical procedure. The fractional cumulative fission yield and half-life of $^{135}\mathrm{Te}$ were also determined from the experimental results. Fission yields measured are: $^{131}\mathrm{I}$, (4.2\ifmmode\pm\else\textpm\fi{}0.4)\ifmmode\times\else\texttimes\fi{}${10}^{\ensuremath{-}3}$% independent; $^{132}\mathrm{I}$, (1.74\ifmmode\pm\else\textpm\fi{}0.11)\ifmmode\times\else\texttimes\fi{}${10}^{\ensuremath{-}2}$% independent; $^{133}\mathrm{I}$, 0.176\ifmmode\pm\else\textpm\fi{}0.009% independent; $^{134}\mathrm{I}$, 0.90\ifmmode\pm\else\textpm\fi{}0.08% independent; $^{135}\mathrm{I}$, 0.44\ifmmode\pm\else\textpm\fi{}0.07 fractional independent; $^{135}\mathrm{Te}$, 0.52\ifmmode\pm\else\textpm\fi{}0.07 fractional cumulative. The half-life of $^{135}\mathrm{Te}$ was determined to be 11.2\ifmmode\pm\else\textpm\fi{}2.6 sec.