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Fragment mass distributions from neutron-induced fission of 232Th and 238U have been measured at quasi-monoenergetic neutron beam of the Louvain-la-Neuve cyclotron facility CYCLONE. The measurements have been carried out making use of a multi-section Frisch-gridded ionization chamber. The measurement technique as well as the data processing is described. Preliminary data on primary fragment mass yields are given for an incident neutron energy of 32.8 MeV. [ABSTRACT FROM AUTHOR]

The Detector for Advanced Neutron Capture Experiments (DANCE) is a 4π BaF2 array consisting of 160 active detector elements. The primary purpose of the array is to perform neutron capture cross section measurements on small (>=100 μg) and/or radioactive (<=100 mCi) species. The measurements made possible with this array will be useful in answering outstanding questions in the areas of national security, threat reduction, nuclear astrophysics, advanced reactor design and accelerator transmutation of waste. Since the commissioning of DANCE we have performed neutron capture cross section measurements on a wide array of medium to heavy mass nuclides. Measurements to date include neutron capture cross sections on 241,243Am, neutron capture and neutron-induced fission cross sections and capture-to-fission ratio (α = σγ/σf) for 235U using a new fission-tagging detector as well as neutron capture cross sections for several astrophysics branch-point nuclei. Results from several of these measurements will be presented along with a discussion of additional physics information that can be extracted from the DANCE data. [ABSTRACT FROM AUTHOR]

Prompt fission neutrons and gamma-rays emitted by excited primary fission fragments are indirect probes to the nuclear configurations present near the scission point. By studying detailed characteristics of these quantities, it is shown that one can discriminate between various assumptions regarding the sharing of the free energy at scission among the two fragments. The case of low-energy neutron-induced fission on 235U is studied and interpreted in terms of fission modes. [ABSTRACT FROM AUTHOR]

The mass and kinetic energy distribution of nuclear fragments from thermal neutron-induced fission of 235U(nth,f) have been studied using a Monte-Carlo simulation. Besides reproducing the pronounced broadening in the standard deviation of the kinetic energy at the final fragment mass number around m = 109, our simulation also produces a second broadening around m = 125. These results are in good agreement with the experimental data obtained by Belhafaf et al. and other results on yield of mass. We conclude that the obtained results are a consequence of the characteristics of the neutron emission, the sharp variation in the primary fragment kinetic energy and mass yield curves. We show that because neutron emission is hazardous to make any conclusion on primary quantities distribution of fragments from experimental results on final quantities distributions. [ABSTRACT FROM AUTHOR]

Based on the recently measured cross-section values for the neutron-induced fission of 231Pa and our experience gained with other isotopes, new self consistent neutron cross section calculations for n+231Pa have been performed up to 30 MeV. The results are quite different to the existing evaluations, especially above the first chance fission threshold. © 2005 American Institute of Physics [ABSTRACT FROM AUTHOR]

The future plans of the GANIL/SPIRAL facility related to the SPIRAL∼2 project are presented. In the frame of this project a new superconducting linear driver (LINAG) will deliver a high intensity, 40 MeV deuteron beam as well as a variety of heavy-ion beams with mass over charge ratio equals to 3 and energy up to 14.5 AMeV. Using a carbon converter and the 5 mA deuteron beam, a neutron-induced fission rate is expected be up to 1014 fissions/s for high-density UCx target. In the contribution different schemes of production of intense beams of fission-fragments as: low and high neutron-induced fission, photo-fission and charge-particle-induced fission proposed by several Radioactive Nuclear Beams projects are shortly compared. © 2005 American Institute of Physics [ABSTRACT FROM AUTHOR]