Measurement of /sup 235/U, /sup 238/U, /sup 209/Bi and /sup nat/Pb fission cross sections using quasi-monenergetic neutrons with energies from 30 MeV to 200 MeV

The cross sections for neutron induced fission of /sup 235/U, /sup 238/U, /sup 209/Bi and /sup nat/Pb were measured in the energy range from 30 MeV to 200 MeV using parallel-plate ionization chambers. Proton recoil telescopes and a /sup 238/U ionization chamber were employed for the determination of the incident neutron fluence. With the exception of a few deviating data points, the experimental results for /sup 235/U(n,f), /sup 238/U(n,f) and /sup 209/Bi(n,f) are close to the recommended cross sections.