Angular momentum in fission fragments
(2024) In Physical Review C 109(3).- Abstract
We suggest that the angular momentum in fission fragments is generated by statistical excitation at scission. The magnitude of the angular momentum is determined by excitation energy and shell structure in the level density. Treating the prescission shape evolution as a diffusive process, implemented as a Metropolis walk on a five-dimensional potential-energy surface, the average magnitudes of the fission fragment angular momenta are calculated for U235(nth,f), assuming that they are perpendicular to the fission axis. The sawtooth behavior of the average angular momentum magnitude as function of mass number is discussed in connection with the similar observed behavior of the average neutron multiplicity, and a good understanding is... (More)
We suggest that the angular momentum in fission fragments is generated by statistical excitation at scission. The magnitude of the angular momentum is determined by excitation energy and shell structure in the level density. Treating the prescission shape evolution as a diffusive process, implemented as a Metropolis walk on a five-dimensional potential-energy surface, the average magnitudes of the fission fragment angular momenta are calculated for U235(nth,f), assuming that they are perpendicular to the fission axis. The sawtooth behavior of the average angular momentum magnitude as function of mass number is discussed in connection with the similar observed behavior of the average neutron multiplicity, and a good understanding is achieved. The magnitudes of the angular momenta of light and heavy fragments are found to have a weak negative correlation, in accordance with recent experimental results. This correlation arises from the microcanonical sharing of excitation energy by the fragments at scission, where each energy provides a distribution of angular momenta.
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- author
- Døssing, T. LU ; Åberg, S. LU ; Albertsson, M. LU ; Carlsson, B. G. LU and Randrup, J. LU
- organization
- publishing date
- 2024
- type
- Contribution to journal
- publication status
- published
- subject
- in
- Physical Review C
- volume
- 109
- issue
- 3
- article number
- 034615
- publisher
- American Physical Society
- external identifiers
-
- scopus:85188507069
- ISSN
- 2469-9985
- DOI
- 10.1103/PhysRevC.109.034615
- language
- English
- LU publication?
- yes
- id
- fa138f47-d918-47b0-a35f-b61fc371385d
- date added to LUP
- 2024-04-19 09:58:18
- date last changed
- 2024-04-19 09:59:42
@article{fa138f47-d918-47b0-a35f-b61fc371385d,
abstract = {{<p>We suggest that the angular momentum in fission fragments is generated by statistical excitation at scission. The magnitude of the angular momentum is determined by excitation energy and shell structure in the level density. Treating the prescission shape evolution as a diffusive process, implemented as a Metropolis walk on a five-dimensional potential-energy surface, the average magnitudes of the fission fragment angular momenta are calculated for U235(nth,f), assuming that they are perpendicular to the fission axis. The sawtooth behavior of the average angular momentum magnitude as function of mass number is discussed in connection with the similar observed behavior of the average neutron multiplicity, and a good understanding is achieved. The magnitudes of the angular momenta of light and heavy fragments are found to have a weak negative correlation, in accordance with recent experimental results. This correlation arises from the microcanonical sharing of excitation energy by the fragments at scission, where each energy provides a distribution of angular momenta.</p>}},
author = {{Døssing, T. and Åberg, S. and Albertsson, M. and Carlsson, B. G. and Randrup, J.}},
issn = {{2469-9985}},
language = {{eng}},
number = {{3}},
publisher = {{American Physical Society}},
series = {{Physical Review C}},
title = {{Angular momentum in fission fragments}},
url = {{http://dx.doi.org/10.1103/PhysRevC.109.034615}},
doi = {{10.1103/PhysRevC.109.034615}},
volume = {{109}},
year = {{2024}},
}