Angular distribution in the neutron-induced fission of actinides

Above 1 MeV of incident neutron energy the fission fragment angular distribution (FFAD) has generally a strong anisotropic behavior due to the combination of the incident orbital momentum and the intrinsic spin of the fissioning nucleus. This effect has to be taken into account for the efficiency...

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Номзүйн дэлгэрэнгүй
Үндсэн зохиолч: Meaze, AKM Moinul Haque
Формат: Өгүүллэг
Хэл сонгох:англи
Хэвлэсэн: EDP Sciences 2025
Онлайн хандалт:https://repository.auw.edu.bd/handle/123456789/935
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author Meaze, AKM Moinul Haque
author_facet Meaze, AKM Moinul Haque
author_sort Meaze, AKM Moinul Haque
collection institutional Repository
description Above 1 MeV of incident neutron energy the fission fragment angular distribution (FFAD) has generally a strong anisotropic behavior due to the combination of the incident orbital momentum and the intrinsic spin of the fissioning nucleus. This effect has to be taken into account for the efficiency estimation of devices used for fission cross section measurements. In addition it bears information on the spin deposition mechanism and on the structure of transitional states. We designed and constructed a detection device, based on Parallel Plate Avalanche Counters (PPAC), for measuring the fission fragment angular distributions of several isotopes, in particular 232Th. The measurement has been performed at n_TOF at CERN taking advantage of the very broad energy spectrum of the neutron beam. Fission events were recognized by back to back detection in coincidence in two position-sensitive detectors surrounding the targets. The detection efficiency, depending mostly on the stopping of fission fragments in backings and electrodes, has been computed with a Geant4 simulation and validated by the comparison to the measured case of 235U below 3 keV where the emission is isotropic. In the case of 232Th, the result is in good agreement with previous data below 10 MeV, with a good reproduction of the structures associated to vibrational states and the opening of second chance fission. In the 14 MeV region our data are much more accurate than previous ones which are broadly scattered.
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spelling 123456789-9352026-02-18T06:15:31Z Angular distribution in the neutron-induced fission of actinides Meaze, AKM Moinul Haque Above 1 MeV of incident neutron energy the fission fragment angular distribution (FFAD) has generally a strong anisotropic behavior due to the combination of the incident orbital momentum and the intrinsic spin of the fissioning nucleus. This effect has to be taken into account for the efficiency estimation of devices used for fission cross section measurements. In addition it bears information on the spin deposition mechanism and on the structure of transitional states. We designed and constructed a detection device, based on Parallel Plate Avalanche Counters (PPAC), for measuring the fission fragment angular distributions of several isotopes, in particular 232Th. The measurement has been performed at n_TOF at CERN taking advantage of the very broad energy spectrum of the neutron beam. Fission events were recognized by back to back detection in coincidence in two position-sensitive detectors surrounding the targets. The detection efficiency, depending mostly on the stopping of fission fragments in backings and electrodes, has been computed with a Geant4 simulation and validated by the comparison to the measured case of 235U below 3 keV where the emission is isotropic. In the case of 232Th, the result is in good agreement with previous data below 10 MeV, with a good reproduction of the structures associated to vibrational states and the opening of second chance fission. In the 14 MeV region our data are much more accurate than previous ones which are broadly scattered. 2025-08-04T12:09:15Z 2025-08-04T12:09:15Z 2013 Article https://repository.auw.edu.bd/handle/123456789/935 en application/pdf EDP Sciences
spellingShingle Meaze, AKM Moinul Haque
Angular distribution in the neutron-induced fission of actinides
title Angular distribution in the neutron-induced fission of actinides
title_full Angular distribution in the neutron-induced fission of actinides
title_fullStr Angular distribution in the neutron-induced fission of actinides
title_full_unstemmed Angular distribution in the neutron-induced fission of actinides
title_short Angular distribution in the neutron-induced fission of actinides
title_sort angular distribution in the neutron induced fission of actinides
url https://repository.auw.edu.bd/handle/123456789/935
work_keys_str_mv AT meazeakmmoinulhaque angulardistributionintheneutroninducedfissionofactinides