High-resolution study of Np fission cross section from 5 eV to 1 MeV
5eVから1MeVまでのNp核分裂断面積の高分解能測定
Furman, W.*; Cennini, P.*; Ketlerov, V.*; Goverdovski, A.*; Konovalov, V.*; Abbondanno, U.*; Aerts, G.*; lvarez, H.*; Alvarez-Velarde, F.*; Andriamonje, S.*; Andrzejewski, J.*; Assimakopoulos, P.*; Audouin, L.*; Badurek, G.*; Baumann, P.*; Becvr, F.*; Benlliure, J.*; Berthoumieux, E.*; Calvio, F.*; Cano-Ott, D.*; Capote, R.*; Carrillo de Albornoz, A.*; 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.*; Durn, I.*; Embid-Segura, M.*; Ferrant, L.*; Ferrari, A.*; Ferreira-Marques, R.*; Fitzpatrick, L.*; Frais-Koelbl, H.*; 藤井 香織*; Guerrero, C.*; Goncalves, I.*; Gallino, R.*; Gonzalez-Romero, E.*; Gramegna, F.*; Griesmayer, E.*; Gunsing, F.*; Haas, B.*; Haight, R.*; Heil, M.*; Herrera-Martinez, A.*; 井頭 政之*; Isaev, S.*; Jericha, E.*; Kadi, Y.*; Kppeler, F.*; Karamanis, D.*; Karadimos, D.*; Kerveno, M.*; Koehler, P.*; Kolokolov, D.*; Kossionides, E.*; Krtika, 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.*; 大島 真澄; 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.*
Furman, W.*; Cennini, P.*; Ketlerov, V.*; Goverdovski, A.*; Konovalov, V.*; Abbondanno, U.*; Aerts, G.*; lvarez, H.*; Alvarez-Velarde, F.*; Andriamonje, S.*; Andrzejewski, J.*; Assimakopoulos, P.*; Audouin, L.*; Badurek, G.*; Baumann, P.*; Becvr, F.*; Benlliure, J.*; Berthoumieux, E.*; Calvio, F.*; Cano-Ott, D.*; Capote, R.*; Carrillo de Albornoz, A.*; 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.*; Durn, I.*; Embid-Segura, M.*; Ferrant, L.*; Ferrari, A.*; Ferreira-Marques, R.*; Fitzpatrick, L.*; Frais-Koelbl, H.*; Fujii, Kaori*; Guerrero, C.*; Goncalves, I.*; Gallino, R.*; Gonzalez-Romero, E.*; Gramegna, F.*; Griesmayer, E.*; Gunsing, F.*; Haas, B.*; Haight, R.*; Heil, M.*; Herrera-Martinez, A.*; Igashira, Masayuki*; Isaev, S.*; Jericha, E.*; Kadi, Y.*; Kppeler, F.*; Karamanis, D.*; Karadimos, D.*; Kerveno, M.*; Koehler, P.*; Kolokolov, D.*; Kossionides, E.*; Krtika, 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, Masumi; 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.*
CERNのn_TOF施設において一連のNp核分裂断面積測定を行った。高速イオンチェンバーを核分裂生成核種の検出に用いた。全実験誤差はほぼ3%であった。5eVから1MeVの中性子エネルギーでの実験解析は、ENDF/B-VI評価値からの系統的なずれを示した。この差は5eV2keVの領域の分離共鳴ではファクター3に達し、以前の測定と一致することがわかった。閾値近傍においては6-7%の同様の不一致が見られた。このエネルギー領域はADSあるいはFBRでのNpの核変換にとって重要であり、Npの核データの再評価が必要であるとの結論を得た。
A series of measurements of Np fission cross section have been performed at the CERN spallation neutron source facility n_TOF. A fast ionization chamber was used as a fission fragment detector. Total experimental uncertainties are determined to be at the level of 3%. Analysis of experimental data in the neutron energy from 5 eV to 1 MeV showed a systematic deviation from the evaluated data (ENDF/B-VI). This discrepancy amounts to up to the factor of 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. 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 is required.