Nota de FísicaPublicado
Absolute Photofission Cross Section of , , , , and Nuclei by Monochromatic and Pol
J. B. Martins; E. L. Moreira; O. A. P. Tavares; J. L. Vieira; L. Casano; A. D Angelo; C. Schaerf; M. L. Terranova; D. Babusci; B. Girolami
1990
Datos de la publicación
- Autores
- J. B. Martins; E. L. Moreira; O. A. P. Tavares; J. L. Vieira; L. Casano; A. D Angelo; C. Schaerf; M. L. Terranova; D. Babusci; B. Girolami
- Tipo
- Nota de Física
- Estado
- Publicado
- Fecha de publicación
- 1990
- Descripción
- Absolute cross section measurements for the photofission reactions of <math>^{197}Au\,\!</math> , <math>^{nat}pb\,\!</math>, <math>^{209}Bi\,\!</math> , <math>^{232}Th\,\!</math>, <math>^{238}U\,\!</math>, and <math>^{235}U\,\!</math> nuclei have been performed at an incident photon energy of <math>69 MeV\,\!</math> using the monochromatic and polarized LADON photon beams and dielectric fission-track detectors. Nuclear fissility values have been obtained and results are in agreement with those from other laboratories, although in some cases discrepancies are observed between, one other. For nuclei in the region of the actinides the fissility resulted to be <math> \gtrsim 0.4\,\!</math>, while for <math>Au\,\!</math>, <math>Pb\,\!</math> and <math>Bi\,\!</math> nuclei it amounts to <math> \sim 10^{-3} -10^{-2}\,\!</math> only. Results have been interpreted in terms of the primary Levinger's quasi-deuteron nuclear photoabsorption followed by a mechanism of evaporation-fission competition for the excited nuclei. Shell effects have been taken into account, and they are clearly manifested when fissility is evaluated. The influence of photon polarization on photofission of <math>^{238}U\,\!</math> has been also investigated, and results have shown isotropy in the fragment azimuthal distribution.
- Año
- 1990
- Número
- CBPF-NF-025/90
- Vínculo con tesis
- No
- Vínculo con beca
- No