Nuclear Charge Distribution in Fission:Rb92andRb93Independent Yields

The fractional independent yields of ${\mathrm{Rb}}^{92}$ and ${\mathrm{Rb}}^{93}$ from thermal-neutron fission of ${\mathrm{U}}^{235}$ have been determined to be 0.62±0.16 and 0.59±0.08, respectively. These values agree with those predicted from Gaussian representations of nuclear charge dispersion for $A=92\mathrm{}$ and $A=93\mathrm{}$. Newly determined half-life values are 4.1±0.3 sec for ${\mathrm{Rb}}^{92}$ and 5.1±0.3 sec for ${\mathrm{Rb}}^{93}$. The experimental method involved rapid separation of rubidium and strontium fission products by adsorption of strontium on solid strontium carbonate and subsequent radiochemical determination of yttrium descendants.