학술논문

Measurement of the 235U(n,f) cross section relative to the 6Li(n,t) and 10B(n,alpha) standards from thermal to 170 keV neutron energy range at n_TOF
Document Type
Working Paper
Author
Amaducci, S.Cosentino, L.Barbagallo, M.Colonna, N.Mengoni, A.Massimi, C.Meo, S. LoFinocchiaro, P.Aberle, O.Andrzejewski, J.Audouin, L.Bacak, M.Balibrea, J.Bečvář, F.Berthoumieux, E.Billowes, J.Bosnar, D.Brown, A.Caamaño, M.Calviño, F.Calviani, M.Cano-Ott, D.Cardella, R.Casanovas, A.Cerutti, F.Chen, Y. H.Chiaveri, E.Cortés, G.Cortés-Giraldo, M. A.Damone, L. A.Diakaki, M.Domingo-Pardo, C.Dressler, R.Dupont, E.Durán, I.Fernández-Domínguez, B.Ferrari, A.Ferreira, P.Furman, V.Göbel, K.García, A. R.Gawlik, A.Gilardoni, S.Glodariu, T.Gonçalves, I. F.González-Romero, E.Griesmayer, E.Guerrero, C.Gunsing, F.Harada, H.Heinitz, S.Heyse, J.Jenkins, D. G.Jericha, E.Käppeler, F.Kadi, Y.Kalamara, A.Kavrigin, P.Kimura, A.Kivel, N.Knapova, I.Kokkoris, M.Krtička, M.Kurtulgil, D.Leal-Cidoncha, E.Lederer, C.Leeb, H.Lerendegui-Marco, J.Lonsdale, S. J.Macina, D.Manna, A.Marganiec, J.Martínez, T.Masi, A.Mastinu, P.Mastromarco, M.Maugeri, E. A.Mazzone, A.Mendoza, E.Milazzo, P. M.Mingrone, F.Musumarra, A.Negret, A.Nolte, R.Oprea, A.Patronis, N.Pavlik, A.Perkowski, J.Porras, I.Praena, J.Quesada, J. M.Radeck, D.Rauscher, T.Reifarth, R.Rubbia, C.Ryan, J. A.Sabaté-Gilarte, M.Saxena, A.Schillebeeckx, P.Schumann, D.Sedyshev, P.Smith, A. G.Sosnin, N. V.Stamatopoulos, A.Tagliente, G.Tain, J. L.Tarifeño-Saldivia, A.Tassan-Got, L.Valenta, S.Vannini, G.Variale, V.Vaz, P.Ventura, A.Vlachoudis, V.Vlastou, R.Wallner, A.Warren, S.Weiss, C.Woods, P. J.Wright, T.Žugec, P.
Source
Subject
Nuclear Experiment
High Energy Physics - Experiment
Language
Abstract
The 235U(n,f) cross section was measured in a wide energy range at n_TOF relative to 6Li(n,t) and 10B(n,alpha), with high resolution and in a wide energy range, with a setup based on a stack of six samples and six silicon detectors placed in the neutron beam. This allowed us to make a direct comparison of the reaction yields under the same experimental conditions, and taking into account the forward/backward emission asymmetry. A hint of an anomaly in the 10{\div}30 keV neutron energy range had been previously observed in other experiments, indicating a cross section systematically lower by several percent relative to major evaluations. The present results indicate that the evaluated cross section in the 9{\div}18 keV neutron energy range is indeed overestimated, both in the recent updates of ENDF/B-VIII.0 and of the IAEA reference data. Furthermore, these new high-resolution data confirm the existence of resonance-like structures in the keV neutron energy region. The new, high accuracy results here reported may lead to a reduction of the uncertainty in the 1{\div}100 keV neutron energy region. Finally, the present data provide additional confidence on the recently re-evaluated cross section integral between 7.8 and 11 eV.
Comment: 22 pages, 20 figures, submitted to PRC