The \̄gnp values for neutron fission of 232Th near threshold

doi:10.1016/0375-9474(77)90248-2

Nuclear Physics A

Volume 285, Issue 2, 25 July 1977, Pages 217-221

https://doi.org/10.1016/0375-9474(77)90248-2 Get rights and content

Abstract

The average number of prompt neutrons emitted per fission, $ν_{p}$ , for ²³²Th(n, f) has been measured between 1.35 and 2.1 MeV. No large maximum in $ν_{p}$ at about 1.4 MeV was seen. The behaviour of $ν_{p}$ and of $E_{K}$ fs, the average total fragment kinetic energy, have been calculated using both a double-humped and triple-humped fission potential barrier. Significant disagreement with existing $E_{K}$ data for ²³²Th(n, f) is apparent.

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Measurements are presented of the photofission and photoneutron cross sections of ²⁴¹Am and of the mean number $v$ of neutrons per fission between 5 and 10 MeV. The measurements were carried out using a bremsstrahlung beam generated by the Harwell electron linear accelerator HELIOS and a 1.5 g metallic ²⁴¹Am target. Neutron multiplicity distributions were recorded using a high-efficiency neutron detector. Yield measurements made in steps of 50 keV show possible evidence for a resonance at 6.1 MeV in the photofission cross section, but the statistical significance is not high.
Fission fragment velocities, masses, and energies from 232Th(n, f) in the resonance-energy region
1992, Nuclear Physics, Section A
Fragment velocities, masses, and energies from neutron-induced fission of ²³²Th were measured at various neutron energies in the subthreshold-resonance region around E_n ≅ 1.6 MeV and above threshold with good neutron-energy resolution. These quantities were obtained by three different methods using two different types of detectors, namely parallel plate avalanche counters for time of flight, and surface-barrier detectors for time of flight and pulse height measurements. Comparison of the different results and a careful error analysis clearly exhibit the limitation in resolution due to methodical uncertainties. Within these limits, none of the measured quantities shows dependencies on neutron energy.
Comparison of different methods for the determination of fission fragment velocity, mass, and energy distributions for 232Th(n, f)
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^†: Present address: Department of Science, Ionospheric Prediction Service, PO Box 702, Darlinghurst, NSW 2010, Australia.

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Nuclear Physics A

Abstract

References (14)

Nucl. Phys.

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J. Nucl. Energy

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Nucl. Phys.

At. Energy Rev.

Cited by (12)

Photofission and photoneutron measurements on <sup>241</sup>Am between 5 and 10 MeV

Fission fragment velocities, masses, and energies from <sup>232</sup>Th(n, f) in the resonance-energy region

Comparison of different methods for the determination of fission fragment velocity, mass, and energy distributions for <sup>232</sup>Th(n, f)

Fission properties of <sup>233</sup>Th

Artificial neural network spectral light curve template for type Ia supernovae and its cosmological constraints

Prompt fission neutron spectra of <sup>238</sup>U and <sup>232</sup>Th above emissive fission threshold