Yavshits S.1, Boykov G.1, Ippolitov V.1, Pakhomov S.1, Roschin A.1, Grudzevich O.2
1V.G.Khlopin Radium Institute, St.-Petersburg, Russia
2Institute of Nuclear Power, Obninsk, Russia
The new approach to the calculation of nucleon induced fission cross sections at 20-200 MeV is presented. The cross sections of multiconfiguration fission (MCF) is calculated as a mixture of (Z,A,p,h,U) configurations formed as a result of fast stage of fission reaction with weights defined by population probability Y of (Z,A) nucleus in (p,h) particle-hole state at excitation energy U. We use intranuclear cascade model to compute the probability Y and precompound-statistical model for calculation of fission and de-excitation cross section from state (Z,A,p,h,U). Calculated results are presented for two absorption cross sections obtained with two optical model parameters sets. Up to 15 fissioning nuclei in 10 (p,h) states at wide excitation region were taken into account in calculation.
nucleon induced fission cross sections, the cross sections of multiconfiguration fission, intranuclear cascade model, precompound-statistical model, optical model parameters
1. O.Bersillon, «SCAT2 – A Spherical Optical Model Code,» CEA-N-2037, p.111 (1978).
2. A.Bohr and B.R.Mottelson, Kgl. Danske Videnskab. Selskab, Mat. Fyz. Medd. 27, No.16 (1953).
3. T.Tamura, Rev. Mod. Phys. 37 (1965) 679.
4. J.Raynal, «Optical Model and Coupled-Channel Calculations in Nuclear Physics», IAEA SMR-9/8 (1970) p.281.
5. J.Raynal, » Nucleon-Nucleus Optical Model Up To 200 MeV», Proceedings of a Specialists Meeting, 13-15 November 1996, Bruye'res-le–Chatel, France, p.159.
6. Young, IAEA-TECDOC, RIPL,Appendix II, 1998.
7. V.A P.Konshin, JAERI-Research, 95-036 (1995).
8. Poenitz, J.F. Whalen, P, ANL-NDM-80, 8305.
9. Langsford, P,AERE-PR/NP-9,36,6604.
10. K.K. Gudima, S.G. Mashnik, V.D. Toneev, Nucl.Phys. A401 (1983) 329.
11. Uhl M. And Strohmaier B Report IRK 76/01. Vienna. 1976; Addena, Sept. 1976.
12. Hauser W. And Feshbach H. Phys. Rev. 1952. V.87. P.366.
13. Moldauer P.A. Phys. Rev. 1964. V.135. P.642.
14. Handbook for calculations of nuclear reaction data IAEA-TECDOC-1034, Vienna, 1998.