High-resolution study of Np-237 fission cross section from 5 eV to 1 MeV
Author
Furman, W.
Cennini, P.
Ketlerov, V.
Goverdovski, A.
Konovalov, V.
Abbondanno, U.
Aerts, G.
Alvarez, H.
Alvarez-Velarde, F.
Andriamonje, S.
Andrzejewski, J.
Assimakopoulos, P.
Audouin, L.
Badurek, G.
Baumann, P.
Becvar, F.
Benlliure, J.
Berthoumieux, E.
Calvino, F.
Cano-Ott, D.
Capote, R.
de Albornoz, A.C.
Chepel, V.
Chiaveri, E.
Colonna, N.
Cortes, G.
Cortina, D.
Couture, A.
Cox, J.
David, S.
Dolfini, R.
Domingo-Pardo, C.
Dorochenko, A.
Dridi, W.
Duran, R.B.
Embid-Segura, M.
Ferrant, L.
Ferrari, A.
Ferreira-Marques, R.
Fitzpatrick, L.
Frais-Koelbl, H.
Fujii, K.
Guerrero, C.
Goncalves, I. F.
Gallino, R.
Gonzalez-Romero, E.
Gramegna, F.
Griesmayer, E.
Gunsing, F.
Haas, B.
Haight, R.
Heil, M.
Herrera-Martinez, A.
Igashira, M.
Isaev, S.
Jericha, E.
Kadi, Y.
Kappeler, F.
Karamanis, D.
Karadimos, D.
Kerveno, M.
Koehler, P.
Kolokolov, D.
Kossionides, E.
Krticka, M.
Lamboudis, C.
Leeb, H.
Lindote, A.
Lopes, I.
Lozano, M.
Lukic, S.
Marganiec, J.
Marques, L.
Marrone, S.
Mastinu, P.
Mengoni, A.
Milazzo, P.M.
Moreau, C.
Mosconi, M.
Neves, F.
Oberhummer, H.
O'Brien, S.
Oshima, M.
Pancin, J.
Papachristodoulou, C.
Papadopoulos, C.
Paradela, C.
Patronis, N.
Pavlik, A.
Pavlopoulos, P.
Perrot, L.
Plag, R.
Plompen, A.
Plukis, A.
Poch, A.
Pretel, C.
Quesada, J.
Rauscher, T.
Reifarth, R.
Rosetti, M.
Rubbia, C.
Rudolf, G.
Rullhusen, P.
Salgado, J.
Sarchiapone, L.
Sedysheva, M.
Stephan, C.
Tagliente, G.
Tain, J. L.
Tassan-Got, L.
Tavora, L.
Terlizzi, R.
Vannini, G.
Vaz, P.
Ventura, A.
Villamarin, D.
Vincente, M.C.
Vlachoudis, V.
Vlastou, R.
Voss, F.
Wendler, H.
Wiescher, M.
Wisshak, K.
Attention
2299/14218
Abstract
A series of measurements of Np-237 fission cross section have been performed at the CERN spallation neutron facility n_TOF which covers a wide energy range from 1 eV up to 250 MeV. A fast ionization chamber (FIC) was used as a fission fragment detector with registration efficiency of not less than 97%. Particular attention was paid to correct the fission cross section with use of U-235 standard. Total experimental uncertainties are determined to be at the level of 3%. Analysis of the experimental data in the restricted neutron energy from 5 eV up to I MeV showed a systematic deviation from evaluated data (ENDF/B-VI). This discrepancy amounts to up to a factor 3 for resolved resonances in the neutron energy range of 5 eV - 2 KeV, and is in good agreement with some previous experiments. A similar disagreement at the level of 6-7% was found for higher energies around the threshold (E-n = 300 keV-1 MeV). This energy range is essential for the transmutation of neptunium in ADS or fast reactors. It is concluded that an updated evaluation of nuclear data for. Np-237 is required.