Abstract
The photofission cross section of was measured in the energy range 250–1200 MeV using a monochromatic tagged photon beam and a parallel-plate avalanche detector. The nuclear photofissility was obtained by measuring simultaneously and in the same energy range the photofission cross section of and assuming a photofissility equal to one for . It was found that, contrary to the case for heavier actinides, the photofissility value does not saturate up to 1200 MeV. Rather, it lies between 0.6 and 0.8, and shows a weak energy dependence: it increases by about 15% over an interval of 1 GeV. A comparison of these experimental findings with the predictions of an intranuclear-cascade Monte Carlo calculation is given.
- Received 9 April 1993
DOI:https://doi.org/10.1103/PhysRevC.48.1785
©1993 American Physical Society