Effect of fission dynamics on the spectra and multiplicities of prompt fission neutrons

Conference · Tue Jan 01 04:00:00 EST 1985

DOI:https://doi.org/10.1080/00337578608208336· OSTI ID:5468675

Nix, J R; Madland, D G; Sierk, A J

With the goal of examining their effect on the spectra and multiplicities of the prompt neutrons emitted in fission, we discuss recent advances in a unified macroscopic-microscopic description of large-amplitude collective nuclear dynamics. The conversion of collective energy into single-particle excitation energy is calculated for a new surface-plus-window dissipation mechanism. By solving the Hamilton equations of motion for initial conditions appropriate to fission, we obtain the average fission-fragment translational kinetic energy and excitation energy. The spectra and multiplicities of the emitted neutrons, which depend critically upon the average excitation energy, are then calculated on the basis of standard nuclear evaporation theory, taking into account the average motion of the fission fragments, the distribution of fission-fragment residual nuclear temperature, the energy dependence of the cross section for the inverse process of compound-nucleus formation, and the possibility of multiple-chance fission. Some illustrative comparisons of our calculations with experimental data are shown.

• Research Organization: Los Alamos National Lab., NM (USA)
• DOE Contract Number: W-7405-ENG-36
• OSTI ID: 5468675
• Report Number(s): LA-UR-85-1731; CONF-850507-27; ON: DE85012727
• Country of Publication: United States
• Language: English

Related Subjects

652026 -- Nuclear Properties & Reactions
A=220 & above
Experimental-- Spontaneous & Induced Fission-- (-1987)
653006* -- Nuclear Theory-- Spontaneous & Induced Fission
73 NUCLEAR PHYSICS AND RADIATION PHYSICS
ACTINIDE ISOTOPES
ACTINIDE NUCLEI
ALPHA DECAY RADIOISOTOPES
BARYONS
COLLECTIVE EXCITATIONS
DATA
DIFFERENTIAL EQUATIONS
DISSIPATION FACTOR
DYNAMICS
ELEMENTARY PARTICLES
ENERGY SPECTRA
ENERGY-LEVEL TRANSITIONS
EQUATIONS
EQUATIONS OF MOTION
EVAPORATION MODEL
EVEN-ODD NUCLEI
EXCITATION
FERMIONS
FISSION
FISSION FRAGMENTS
FISSION NEUTRONS
HADRONS
HEAVY NUCLEI
INFORMATION
ISOMERIC TRANSITION ISOTOPES
ISOTOPES
MATHEMATICAL MODELS
MECHANICS
MINUTES LIVING RADIOISOTOPES
MULTIPLICITY
NEUTRONS
NUCLEAR FRAGMENTS
NUCLEAR MODELS
NUCLEAR REACTIONS
NUCLEI
NUCLEONS
NUMERICAL DATA
PARTIAL DIFFERENTIAL EQUATIONS
PROMPT NEUTRONS
RADIOISOTOPES
SPECTRA
THEORETICAL DATA
URANIUM 235
URANIUM ISOTOPES
YEARS LIVING RADIOISOTOPES