Influence of the odd neutron on the fragment characteristics in the photofission of 235U

doi:10.1016/S0375-9474(96)00475-7

Nuclear Physics A

Volume 615, Issue 2, 24 March 1997, Pages 198-206

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Abstract

Cumulative and independent post-neutron product yields were measured for the photofission on ²³⁵U with 6.5, 7.0, and 8.4 MeV bremsstrahlung, applying γ-spectrometric methods on catcherfoils and pneumatically transported ²³⁵U-samples. The independent yields for the heavy (A = 128–149) fragments were deduced. Post-neutron mass and isotonic yield distributions were studied together with the elemental yield distributions and the proton odd-even effect. The mass distribution shows about an equal yield for the mass regions around A = 134 (N = 82) and A = 142 (N = 86–88). The proton odd-even effect for the fission of this odd-A nucleus remains at a constant value δ_p = 25% in the studied compound nucleus excitation energy region, indicating that the odd neutron does not influence the energy transfer between the different degrees of freedom during the descent from saddle to scission point in a substantial way.

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¹: Research director National Fund for Scientific Research. Corresponding author.

²: Present address: SCK-CEN Mol, Belgium.

³: Research director National Fund for Scientific Research.

⁴: Present address: Physics Institute, São Paulo, Brazil.

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Nuclear Physics A

Abstract

References (12)

Nucl. Phys. A

Nucl. Phys. A

Nucl. Phys. A

At. Data and Nucl. Data Tables

Phys. Rep.

Cited by (8)

Measurement of fission product yields in the quasi-mono-energetic neutron-induced fission of <sup>238</sup>U

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Nuclear Data Sheets for A = 137

Radionuclide metrology: confidence in radioactivity measurements

Fission product yield distribution in the 12, 14, and 16 MeV bremsstrahlung-induced fission of <sup>232</sup>Th

Mass distribution in the 50-, 60-, and 70-MeV bremsstrahlung-induced fission of 232Th