RECOIL STUDIES OF HIGH-ENERGY FISSION OF BISMUTH AND TANTALUM

The recoil properties of a number of fission fragnnents formed in 450- Mev proton bombardment of Bi and Ta have been investigated radiochemically. The raages of the fragments emitted in the direction of, and perpendicular to the beam were measured. The kinetic energies of the fragments were obtained from the measured ranges using a previously determined range-energy relation. The total average kinetic energy released in fission was found to be 111 Mev for Bi and 96 Mev for Ta. The energy deposited in the target nuclei for processes leading to the observed fragments was obtained from the forward-backward seyrametry and the other measured recoil parameters, and a momentum-deposition energy relation from recent Monte Carlo calculations. The average deposition energy in the fission of Bi and Ta was found to be 160 Mev and 190 Mev, respectively. (auth)