Measurement of the $^{239}$Pu(n,f)/$^{235}$U(n,f) Cross-Section Ratio with the NIFFTE fission Time Projection Chamber

L. Snyder; M. Anastasiou; N. S. Bowden; J. Bundgaard; R. J. Casperson; D. A. Cebra; T. Classen; D. H. Dongwi; N. Fotiades; J. Gearhart; V. Geppert-Kleinrath; U. Greife; C. Hagmann; M. Heffner; D. Hensle; D. Higgins; L. D. Isenhower; K. Kazkaz; A. Kemnitz; J. King; J. L. Klay; J. Latta; E. Leal-Cidoncha; W. Loveland; J. A. Magee; B. Manning; M. P. Mendenhall; M. Monterial; S. Mosby; D. Neudecker; C. Prokop; S. Sangiorgio; K. T. Schmitt; B. Seilhan; F. Tovesson; R. S. Towell; N. Walsh; T. S. Watson; L. Yao; W. Younes

arXiv · 2107.02881

Measurement of the $^{239}$Pu(n,f)/$^{235}$U(n,f) Cross-Section Ratio with the NIFFTE fission Time Projection Chamber

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Abstract

The $^{239}$Pu(n,f)/$^{235}$U(n,f) cross-section ratio has been measured with the fission Time Projection Chamber (fissionTPC) from 100 keV to 100 MeV. The fissionTPC provides three-dimensional reconstruction of fission-fragment ionization profiles, allowing for a precise quantification of measurement uncertainties. The measurement was performed at the Los Alamos Neutron Science Center which provides a pulsed white source of neutrons. The data are recommended to be used as a cross-section ratio shape. A discussion of the status of the absolute normalization and comparisons to ENDF evaluations and previous measurements is included.

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L. Snyder, M. Anastasiou, N. S. Bowden, J. Bundgaard, R. J. Casperson, D. A. Cebra, T. Classen, D. H. Dongwi, N. Fotiades, J. Gearhart, V. Geppert-Kleinrath, U. Greife, C. Hagmann, M. Heffner, D. Hensle, D. Higgins, L. D. Isenhower, K. Kazkaz, A. Kemnitz, J. King, J. L. Klay, J. Latta, E. Leal-Cidoncha, W. Loveland, J. A. Magee, B. Manning, M. P. Mendenhall, M. Monterial, S. Mosby, D. Neudecker, C. Prokop, S. Sangiorgio, K. T. Schmitt, B. Seilhan, F. Tovesson, R. S. Towell, N. Walsh, T. S. Watson, L. Yao, W. Younes. 2021-07-06. Measurement of the $^{239}$Pu(n,f)/$^{235}$U(n,f) Cross-Section Ratio with the NIFFTE fission Time Projection Chamber. https://arxiv.org/abs/2107.02881

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