https://doi.org/10.1140/epja/s10050-026-01834-3
Regular Article - Experimental Physics
Measurement of fission product yields from the 232Th(n, f) and 238U(n, f) reactions at a flux-weighted average energy of 9.63 MeV
1
Radiochemistry Division, Bhabha Atomic Research Centre, 400 085, Mumbai, India
2
Department of Statistics, Manipal Academy of Higher Education, 576 104, Manipal, India
3
Maharaja Sayajirao University of Baroda, 390 002, Vadodara, India
4
Institute for Plasma Research, 382428, Gandhinagar, India
5
Nuclear Physics Division, Bhabha Atomic Research Centre, 400 085, Mumbai, India
a
This email address is being protected from spambots. You need JavaScript enabled to view it.
Received:
22
September
2025
Accepted:
9
March
2026
Published online:
7
April
2026
Abstract
The cumulative yields of various fission products from the 232Th(n, f) and 238U(n, f) reactions at an average energy of 9.63 MeV have been determined by using an off-line γ-ray spectrometry technique. The measurement of fission product yields are relative to the fission product monitor 92Sr in the 232Th(n, f) reaction and 135I in the 238U(n, f)reaction. The neutron beam was produced via the 7Li(p, n) reaction with the proton energy of 17 MeV. From the cumulative yields, mass chain yields were obtained by applying charge distribution correction. The peak-to-valley (P/V) ratio, the average value of light mass (<AL>), heavy mass (<AH>) and the average number of neutrons (<ν>) were obtained. From the data of the present work and literature it was found that (i) the mass yield distribution in the 238U(n, f) reaction is double-humped, whereas it is triple-humped in the 232Th(n, f) reaction, which is due to the different type of potential energy surface for 233Th* and 239U*. (ii) The yields for A = 133–134, A = 138–139, and A = 143–144 and their complementary products are higher than other fission products due to even–odd effect. (iii) The yields for A = 133–134 are higher in the 238U(n, f) reaction, whereas it is higher for A = 143–144 in the 232Th(n, f) reaction, which was explained based on the standard I and standard II asymmetric mode of fission. (iv)The yield of symmetric products increases with excitation energy, which causes a decreasing trend of peak-to-valley (P/V) ratio. However, at the same excitation energy, the yield of symmetric products is lower and thus the P/V ratio is higher in the 238U(n, f) reaction than in the 232Th(n, f) reaction.
Copyright comment Springer Nature or its licensor (e.g. a society or other partner) holds exclusive rights to this article under a publishing agreement with the author(s) or other rightsholder(s); author self-archiving of the accepted manuscript version of this article is solely governed by the terms of such publishing agreement and applicable law.
Communicated by Jose Benlliure.
© The Author(s), under exclusive licence to Società Italiana di Fisica and Springer-Verlag GmbH Germany, part of Springer Nature 2026
Springer Nature or its licensor (e.g. a society or other partner) holds exclusive rights to this article under a publishing agreement with the author(s) or other rightsholder(s); author self-archiving of the accepted manuscript version of this article is solely governed by the terms of such publishing agreement and applicable law.
