1. Defective fission correlation data from the 2E-2v method
- Author
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Jansson, Kaj, Al-Adili, Ali, Sundén, Erik Andersson, Pomp, Stephan, Göök, Alf, and Oberstedt, Stephan
- Subjects
Physics - Instrumentation and Detectors ,Nuclear Experiment - Abstract
The double-energy double-velocity ($2E$-$2v$) method allows assessing fission-fragment mass yields prior to and after prompt neutron emission with high resolution. It is, therefore, considered as a complementary technique to assess average prompt neutron multiplicity as a function of fragment properties. We have studied the intrinsic features of the $2E$-$2v$ method by means of event-wise generated fission-fragment data and found severe short-comings in the method itself as well as in some common practice of application. We find that the $2E$-$2v$ method leads to large deviations in the correlation between the prompt neutron multiplicity and pre-neutron mass, which deforms and exaggerates the so called `sawtooth' shape of $\bar{\nu}(A)$. We have identified the treatment of prompt neutron emission from the fragments as the origin of the problem. The intrinsic nature of this deficiency, risk to render $2E$-$2v$ experiments much less interesting. We suggest a method to correct the $2E$-$2v$ data, and recommend applying this method to previous data acquired in $2E$-$2v$ experiments, as well., Comment: 5 pages, 5 figures
- Published
- 2017