# Radiochemistry and the Study of Fission

## Abstract

These are slides from a lecture given at UC Berkeley. Radiochemistry has been used to study fission since its discovery. Radiochemical methods are used to determine cumulative mass yields. These measurements have led to the two-mode fission hypothesis to model the neutron energy dependence of fission product yields. Fission product yields can be used for the nuclear forensics of nuclear explosions. The mass yield curve depends on both the fuel and the neutron spectrum of a device. Recent studies have shown that the nuclear structure of the compound nucleus can affect the mass yield distribution. The following topics are covered: In the beginning: the discovery of fission; forensics using fission products: what can be learned from fission products, definitions of R-values and Q-values, fission bases, K-factors and fission chambers, limitations; the neutron energy dependence of the mass yield distribution (the two mode fission hypothesis); the influence of nuclear structure on the mass yield distribution. In summary: Radiochemistry has been used to study fission since its discovery. Radiochemical measurement of fission product yields have provided the highest precision data for developing fission models and for nuclear forensics. The two-mode fission hypothesis provides a description of the neutron energy dependence of themore »

- Authors:

- Los Alamos National Lab. (LANL), Los Alamos, NM (United States)

- Publication Date:

- Research Org.:
- Los Alamos National Lab. (LANL), Los Alamos, NM (United States)

- Sponsoring Org.:
- USDOE National Nuclear Security Administration (NNSA), Office of Defense Nuclear Nonproliferation (NA-20)

- OSTI Identifier:
- 1332211

- Report Number(s):
- LA-UR-16-28775

TRN: US1700717

- DOE Contract Number:
- AC52-06NA25396

- Resource Type:
- Technical Report

- Country of Publication:
- United States

- Language:
- English

- Subject:
- 73 NUCLEAR PHYSICS AND RADIATION PHYSICS; 38 RADIATION CHEMISTRY, RADIOCHEMISTRY, AND NUCLEAR CHEMISTRY; FISSION YIELD; FISSION; FISSION PRODUCTS; RADIOCHEMISTRY; NUCLEAR FORENSICS; MASS; FISSION CHAMBERS; ENERGY DEPENDENCE; DISTRIBUTION; HYPOTHESIS; COMPOUND NUCLEI; NEUTRON SPECTRA; NUCLEAR EXPLOSIONS; NUCLEAR STRUCTURE; NUCLEAR REACTION KINETICS; Q-VALUE; RESONANCE NEUTRONS; MULTIPLICATION FACTORS

### Citation Formats

```
Rundberg, Robert S.
```*Radiochemistry and the Study of Fission*. United States: N. p., 2016.
Web. doi:10.2172/1332211.

```
Rundberg, Robert S.
```*Radiochemistry and the Study of Fission*. United States. doi:10.2172/1332211.

```
Rundberg, Robert S. Mon .
"Radiochemistry and the Study of Fission". United States.
doi:10.2172/1332211. https://www.osti.gov/servlets/purl/1332211.
```

```
@article{osti_1332211,
```

title = {Radiochemistry and the Study of Fission},

author = {Rundberg, Robert S.},

abstractNote = {These are slides from a lecture given at UC Berkeley. Radiochemistry has been used to study fission since its discovery. Radiochemical methods are used to determine cumulative mass yields. These measurements have led to the two-mode fission hypothesis to model the neutron energy dependence of fission product yields. Fission product yields can be used for the nuclear forensics of nuclear explosions. The mass yield curve depends on both the fuel and the neutron spectrum of a device. Recent studies have shown that the nuclear structure of the compound nucleus can affect the mass yield distribution. The following topics are covered: In the beginning: the discovery of fission; forensics using fission products: what can be learned from fission products, definitions of R-values and Q-values, fission bases, K-factors and fission chambers, limitations; the neutron energy dependence of the mass yield distribution (the two mode fission hypothesis); the influence of nuclear structure on the mass yield distribution. In summary: Radiochemistry has been used to study fission since its discovery. Radiochemical measurement of fission product yields have provided the highest precision data for developing fission models and for nuclear forensics. The two-mode fission hypothesis provides a description of the neutron energy dependence of the mass yield curve. However, data is still rather sparse and more work is needed near second and third chance fission. Radiochemical measurements have provided evidence for the importance of nuclear states in the compound nucleus in predicting the mass yield curve in the resonance region.},

doi = {10.2172/1332211},

journal = {},

number = ,

volume = ,

place = {United States},

year = {Mon Nov 14 00:00:00 EST 2016},

month = {Mon Nov 14 00:00:00 EST 2016}

}