Open Access

Federica Mingrone, Cristian Massimi, Gianni Vannini, Nicola Colonna, Frank Gunsing, Petar Žugec, Sebastian Altstadt, Józef Andrzejewski, Laurent Audouin, Massimo Barbagallo, Vicente Bécares, František Bečvář, Fabio Belloni, Eric Berthoumieux, Jonathan Billowes, Damir Bosnar, Markus Brugger, Marco Calviani, Francisco Calviño Tavares, Daniel Cano-Ott, Carlos Carrapiço, Francesco Cerutti, Enrico Chiaveri, Michael Chin, Guillem Pere Cortés Rossell, Miguel Antonio Cortés-Giraldo, Maria Diakaki, César Domingo-Pardo, Ignacio Durán, Rugard Dressler, Christos Eleftheriadis, Alfredo Ferrari, Kevin Fraval, Srinivasan Ganesan, Aczel Regino García Ríos, Giuseppe Giubrone, Isabel Maria Ferro Gonçalves, Enrique Miguel González Romero, Erich Griesmayer, Carlos Guerrero Sánchez, Álvaro Hernández Prieto, David Jenkins, Erwin Jericha, Yacine Kadi, Franz Käppeler, Dimitri Karadimos, Nikolay Kivel, Paul Koehler, Michael Kokkoris, Milan Krtička, Jiří Kroll, Christos Lampoudis, Christoph Langer, Esther Leal Cidoncha, Claudia Lederer, Helmut Leeb, Lou Sai Leong, Sergio Lo Meo, Roberto Losito, Amod Kishore Mallick, Athanasios Manousos, Justyna Marganiec, Trinitario Martı́nez, Pierfrancesco Mastinu, Mario Mastromarco, Emilio Mendoza Cembranos, Alberto Mengoni, Paolo Maria Milazzo, Mihail Mirea, Willy Mondalaers, Carlos Paradela Dobarro, Andreas Pavlik, Jarosław Perkowski, Arjan J. M. Plompen, Javier Praena, José Manuel Quesada Molina, Thomas Rauscher, René Reifarth, Albert Riego Pérez, Maria Soledad Robles Manzano, Carlo Rubbia, Marta Sabaté-Gilarte, Raul Sarmento, Alok Saxena, Peter Schillebeeckx, Stefan Schmidt, Dorothea Schumann, Giuseppe Tagliente, José Luis Taı́n Enríquez, Diego Tarrío Vilas, Laurent Tassan-Got, Andrea Tsinganis, Stanislav Valenta, Vincenzo Variale, Pedro Vaz, Alberto Ventura, Mark J. Vermeulen, Vasilis Vlachoudis, Rosa Vlastou, Anton Wallner, Timothy Ware, Mario Weigand, Christina Weiß, Tobias Wright

• The aim of this work is to provide a precise and accurate measurement of the 238U(n,γ) reaction cross section in the energy region from 1 eV to 700 keV. This reaction is of fundamental importance for the design calculations of nuclear reactors, governing the behavior of the reactor core. In particular, fast reactors, which are experiencing a growing interest for their ability to burn radioactive waste, operate in the high energy region of the neutron spectrum. In this energy region most recent evaluations disagree due to inconsistencies in the existing measurements of up to 15%. In addition, the assessment of nuclear data uncertainty performed for innovative reactor systems shows that the uncertainty in the radiative capture cross section of 238U should be further reduced to 1–3% in the energy region from 20 eV to 25 keV. To this purpose, addressed by the Nuclear Energy Agency as a priority nuclear data need, complementary experiments, one at the GELINA and two at the n_TOF facility, were proposed and carried out within the 7th Framework Project ANDES of the European Commission. The results of one of these 238U(n,γ) measurements performed at the n_TOF CERN facility are presented in this work. The γ-ray cascade following the radiative neutron capture has been detected exploiting a setup of two C6D6 liquid scintillators. Resonance parameters obtained from this work are on average in excellent agreement with the ones reported in evaluated libraries. In the unresolved resonance region, this work yields a cross section in agreement with evaluated libraries up to 80 keV, while for higher energies our results are significantly higher.