# Product yields for the photofission of /sup 238/U with 12-, 15-, 20-, 30-, and 70-MeV bremsstrahlung

## Abstract

Cumulative yields for about 40 mass chains and fractional independent yields of /sup 128/Sn, /sup 128/Sb/sup g/, /sup 131/Te/sup g/, /sup 131/Te/sup m/, /sup 132/I/sup g/, /sup 132/I/sup m/, /sup 134/I, /sup 134/Cs, /sup 135/Xe, and /sup 136/Cs were determined for the photofission of /sup 238/U with 12-, 15-, 20-, 30-, and 70-MeV bremsstrahlung. Changes in the characteristics of the mass distribution are studied. An enhanced yield in the mass region 133-134, decreasing with increasing end-point energy of the bremsstrahlung (E/sub e/), is observed. From the determined independent yields the most probable charges Z/sub p/(E/sub e/) are calculated using the value 0.85 for the width parameter c of the charge distribution as deduced from our results for mass chain 134. The determined Z/sub p/(E/sub e/) values are very well described by the empirical relation of Nethaway except for the mass chain 136. This discrepancy for mass chain 136, which decreases with increasing end-point energy of the bremsstrahlung, is attributed to an abnormal low yield of /sup 136/Cs. Fragment shell effects are discussed. From the isomeric ratios for /sup 131/Te/sup g/-/sup 131/Te/sup m/ and /sup 132/I/sup g/-/sup 132/I/sup m/ average initial fragment spins are calculated using a statistical model analysis.

- Authors:

- Publication Date:

- Research Org.:
- Nuclear Physics Laboratory, Proeftuinstraat 86, B-9000 Gent, Belgium

- OSTI Identifier:
- 6457352

- Resource Type:
- Journal Article

- Journal Name:
- Phys. Rev., C; (United States)

- Additional Journal Information:
- Journal Volume: 19:2

- Country of Publication:
- United States

- Language:
- English

- Subject:
- 73 NUCLEAR PHYSICS AND RADIATION PHYSICS; FISSION FRAGMENTS; SPIN; URANIUM 238 TARGET; PHOTOFISSION; ANTIMONY 128; BREMSSTRAHLUNG; CESIUM 134; CESIUM 136; CHARGE DISTRIBUTION; EXPERIMENTAL DATA; FISSION YIELD; GAMMA SPECTRA; GRAPHS; IODINE 132; IODINE 134; MASS SPECTRA; MEV RANGE 10-100; SHELL MODELS; STATISTICAL MODELS; TELLURIUM 131; TIN 128; XENON 135; ALKALI METAL ISOTOPES; ANGULAR MOMENTUM; ANTIMONY ISOTOPES; BETA DECAY RADIOISOTOPES; BETA-MINUS DECAY RADIOISOTOPES; CESIUM ISOTOPES; DATA; DATA FORMS; DAYS LIVING RADIOISOTOPES; ELECTROMAGNETIC RADIATION; ENERGY RANGE; EVEN-EVEN NUCLEI; EVEN-ODD NUCLEI; FISSION; HOURS LIVING RADIOISOTOPES; INFORMATION; INTERMEDIATE MASS NUCLEI; INTERNAL CONVERSION RADIOISOTOPES; IODINE ISOTOPES; ISOMERIC TRANSITION ISOTOPES; ISOTOPES; MATHEMATICAL MODELS; MEV RANGE; MINUTES LIVING RADIOISOTOPES; NUCLEAR FRAGMENTS; NUCLEAR MODELS; NUCLEAR REACTION YIELD; NUCLEAR REACTIONS; NUCLEI; NUMERICAL DATA; ODD-ODD NUCLEI; PARTICLE PROPERTIES; PHOTONUCLEAR REACTIONS; RADIATIONS; RADIOISOTOPES; SPECTRA; TARGETS; TELLURIUM ISOTOPES; TIN ISOTOPES; XENON ISOTOPES; YEARS LIVING RADIOISOTOPES; YIELDS; 652026* - Nuclear Properties & Reactions, A=220 & above, Experimental- Spontaneous & Induced Fission- (-1987)

### Citation Formats

```
Jacobs, E, Thierens, H, De Frenne, D, De Clercq, A, D'hondt, P, De Gelder, P, and Deruytter, A J.
```*Product yields for the photofission of /sup 238/U with 12-, 15-, 20-, 30-, and 70-MeV bremsstrahlung*. United States: N. p., 1979.
Web. doi:10.1103/PhysRevC.19.422.

```
Jacobs, E, Thierens, H, De Frenne, D, De Clercq, A, D'hondt, P, De Gelder, P, & Deruytter, A J.
```*Product yields for the photofission of /sup 238/U with 12-, 15-, 20-, 30-, and 70-MeV bremsstrahlung*. United States. doi:10.1103/PhysRevC.19.422.

```
Jacobs, E, Thierens, H, De Frenne, D, De Clercq, A, D'hondt, P, De Gelder, P, and Deruytter, A J. Thu .
"Product yields for the photofission of /sup 238/U with 12-, 15-, 20-, 30-, and 70-MeV bremsstrahlung". United States. doi:10.1103/PhysRevC.19.422.
```

```
@article{osti_6457352,
```

title = {Product yields for the photofission of /sup 238/U with 12-, 15-, 20-, 30-, and 70-MeV bremsstrahlung},

author = {Jacobs, E and Thierens, H and De Frenne, D and De Clercq, A and D'hondt, P and De Gelder, P and Deruytter, A J},

abstractNote = {Cumulative yields for about 40 mass chains and fractional independent yields of /sup 128/Sn, /sup 128/Sb/sup g/, /sup 131/Te/sup g/, /sup 131/Te/sup m/, /sup 132/I/sup g/, /sup 132/I/sup m/, /sup 134/I, /sup 134/Cs, /sup 135/Xe, and /sup 136/Cs were determined for the photofission of /sup 238/U with 12-, 15-, 20-, 30-, and 70-MeV bremsstrahlung. Changes in the characteristics of the mass distribution are studied. An enhanced yield in the mass region 133-134, decreasing with increasing end-point energy of the bremsstrahlung (E/sub e/), is observed. From the determined independent yields the most probable charges Z/sub p/(E/sub e/) are calculated using the value 0.85 for the width parameter c of the charge distribution as deduced from our results for mass chain 134. The determined Z/sub p/(E/sub e/) values are very well described by the empirical relation of Nethaway except for the mass chain 136. This discrepancy for mass chain 136, which decreases with increasing end-point energy of the bremsstrahlung, is attributed to an abnormal low yield of /sup 136/Cs. Fragment shell effects are discussed. From the isomeric ratios for /sup 131/Te/sup g/-/sup 131/Te/sup m/ and /sup 132/I/sup g/-/sup 132/I/sup m/ average initial fragment spins are calculated using a statistical model analysis.},

doi = {10.1103/PhysRevC.19.422},

journal = {Phys. Rev., C; (United States)},

number = ,

volume = 19:2,

place = {United States},

year = {1979},

month = {2}

}