# Calculations of the anisotropy of the fission fragment angular distribution and neutron emission multiplicities prescission from Langevin dynamics

## Abstract

The anisotropy of the fission fragment angular distribution defined at the saddle point and the neutron multiplicities emitted prior to scission for fissioning nuclei {sup 224}Th, {sup 229}Np, {sup 248}Cf, and {sup 254}Fm are calculated simultaneously by using a set of realistic coupled two-dimensional Langevin equations, where the (c,h,{alpha}=0) nuclear parametrization is employed. In comparison with the one-dimensional stochastic model without neck variation, our two-dimensional model produces results that are in better agreement with the experimental data, and the one-dimensional model is available only for low excitation energies. Indeed, to determine the temperature of the nucleus at the saddle point, we investigate the neutron emission during nucleus oscillation around the saddle point for different friction mechanisms. It is shown that the neutrons emitted during the saddle oscillation cause the temperature of a fissioning nuclear system at the saddle point to decrease and influence the fission fragment angular distribution.

- Authors:

- Department of Physics, Beijing Normal University, Beijing 100875 (China)

- Publication Date:

- OSTI Identifier:
- 20995133

- Resource Type:
- Journal Article

- Resource Relation:
- Journal Name: Physical Review. C, Nuclear Physics; Journal Volume: 75; Journal Issue: 3; Other Information: DOI: 10.1103/PhysRevC.75.034601; (c) 2007 The American Physical Society; Country of input: International Atomic Energy Agency (IAEA)

- Country of Publication:
- United States

- Language:
- English

- Subject:
- 73 NUCLEAR PHYSICS AND RADIATION PHYSICS; ANGULAR DISTRIBUTION; ANISOTROPY; CALIFORNIUM 248; COMPARATIVE EVALUATIONS; FERMIUM 254; FISSION FRAGMENTS; LANGEVIN EQUATION; MULTIPLICITY; NEPTUNIUM 229; NEUTRON EMISSION; NEUTRONS; ONE-DIMENSIONAL CALCULATIONS; THORIUM 224; TWO-DIMENSIONAL CALCULATIONS

### Citation Formats

```
Jia Ying, and Bao Jingdong.
```*Calculations of the anisotropy of the fission fragment angular distribution and neutron emission multiplicities prescission from Langevin dynamics*. United States: N. p., 2007.
Web. doi:10.1103/PHYSREVC.75.034601.

```
Jia Ying, & Bao Jingdong.
```*Calculations of the anisotropy of the fission fragment angular distribution and neutron emission multiplicities prescission from Langevin dynamics*. United States. doi:10.1103/PHYSREVC.75.034601.

```
Jia Ying, and Bao Jingdong. Thu .
"Calculations of the anisotropy of the fission fragment angular distribution and neutron emission multiplicities prescission from Langevin dynamics". United States.
doi:10.1103/PHYSREVC.75.034601.
```

```
@article{osti_20995133,
```

title = {Calculations of the anisotropy of the fission fragment angular distribution and neutron emission multiplicities prescission from Langevin dynamics},

author = {Jia Ying and Bao Jingdong},

abstractNote = {The anisotropy of the fission fragment angular distribution defined at the saddle point and the neutron multiplicities emitted prior to scission for fissioning nuclei {sup 224}Th, {sup 229}Np, {sup 248}Cf, and {sup 254}Fm are calculated simultaneously by using a set of realistic coupled two-dimensional Langevin equations, where the (c,h,{alpha}=0) nuclear parametrization is employed. In comparison with the one-dimensional stochastic model without neck variation, our two-dimensional model produces results that are in better agreement with the experimental data, and the one-dimensional model is available only for low excitation energies. Indeed, to determine the temperature of the nucleus at the saddle point, we investigate the neutron emission during nucleus oscillation around the saddle point for different friction mechanisms. It is shown that the neutrons emitted during the saddle oscillation cause the temperature of a fissioning nuclear system at the saddle point to decrease and influence the fission fragment angular distribution.},

doi = {10.1103/PHYSREVC.75.034601},

journal = {Physical Review. C, Nuclear Physics},

number = 3,

volume = 75,

place = {United States},

year = {Thu Mar 15 00:00:00 EDT 2007},

month = {Thu Mar 15 00:00:00 EDT 2007}

}