Abstract
The fractional independent yields of , , , and from thermal-neutron fission of have been determined to be 0.0013±0.0002, 0.016±0.004, 0.08±0.02, and 0.29±0.08, respectively. The experimental method involved rapid separation of yttrium and strontium fission products by precipitation of yttrium hydroxide and subsequent radiochemical determination of the yttrium isotopes. Newly determined half-life values are 84±5 sec for and 33±6 sec for . Gaussian curves which satisfactorily represent the nuclear charge dispersion for have standard deviations , respectively. The average value of for ten mass numbers () is 0.59±0.02. For the individual mass numbers, a single Gaussian curve with (full width at half-maximum = 1.56±0.12 charge units) gives a satisfactory representation of nuclear charge dispersion.
- Received 27 January 1966
DOI:https://doi.org/10.1103/PhysRev.146.926
©1966 American Physical Society