High-accuracy determination of the neutron flux at n_TOF

Barbagallo, M.; Guerrero, C.; Tsinganis, A.; Tarrio, D.; Altstadt, S.; Andriamonje, S.; Andrzejewski, J.; Audouin, L.; Becares, V.; Becvar, F.; Belloni, F.; Berthoumieux, E.; Billowes, J.; Boccone, V.; Bosnar, D.; Brugger, M.; Calviani, M.; Calvino, F.; Cano Ott, D.; Carrapico, C.; Cerutti, F.; Chiaveri, E.; Chin, M.; Colonna, N.; Cortes, G.; Cortes Giraldo, M. A.; Diakaki, M.; Domingo Pardo, C.; Duran, I.; Dressler, R.; Dzysiuk, N.; Eleftheriadis, C.; Ferrari, A.; Fraval, K.; Ganesan, S.; Garcia, A. R.; Giubrone, G.; Gobel, K.; Gomez Hornillos, M. B.; Goncalves, I. F.; Gonzalez Romero, E.; Griesmayer, E.; Gunsing, F.; Gurusamy, P.; Hernandez Prieto, A.; Jenkins, D. G.; Jericha, E.; Kadi, Y.; Kappeler, F.; Karadimos, D.; Kivel, N.; Koehler, P.; Kokkoris, M.; Krticka, M.; Kroll, J.; Lampoudis, C.; Langer, C.; Leal Cidoncha, E.; Lederer, C.; Leeb, H.; Leong, L. S.; Losito, R.; Manousos, A.; Marganiec, J.; Martinez, T.; Massimi, Cristian; Mastinu, P. F.; Mastromarco, M.; Meaze, M.; Mendoza, E.; Mengoni, A.; Milazzo, P. M.; Mingrone, Federica; Mirea, M.; Mondalaers, W.; Papaevangelou, T.; Paradela, C.; Pavlik, A.; Perkowski, J.; Plompen, A.; Praena, J.; Quesada, J. M.; Rauscher, T.; Reifarth, R.; Riego, A.; Roman, F.; Rubbia, C.; Sabate Gilarte, M.; Sarmento, R.; Saxena, A.; Schillebeeckx, P.; Schmidt, S.; Schumann, D.; Steinegger, P.; Tagliente, G.; Tain, J. L.; Tassan Got, L.; Valenta, S.; Vannini, Gianni; Variale, V.; Vaz, P.; Ventura, A.; Versaci, R.; Vermeulen, M. J.; Vlachoudis, V.; Vlastou, R.; Wallner, A.; Ware, T.; Weigand, M.; Weiss, C.; Wright, T.; Zugec, P.

doi:10.1140/epja/i2013-13156-x

The neutron flux of the n_TOF facility at CERN was measured, after installation of the new spallation target, with four different systems based on three neutron-converting reactions, which represent accepted cross sections standards in different energy regions. A careful comparison and combination of the different measurements allowed us to reach an unprecedented accuracy on the energy dependence of the neutron flux in the very wide range (thermal to 1 GeV) that characterizes the n_TOF neutron beam. This is a pre-requisite for the high accuracy of cross section measurements at n_TOF. An unexpected anomaly in the neutron-induced fission cross section of U-235 is observed in the energy region between 10 and 30keV, hinting at a possible overestimation of this important cross section, well above currently assigned uncertainties.

M. Barbagallo, C. Guerrero, A. Tsinganis, D. Tarrio, S. Altstadt, S. Andriamonje, et al. (2013). High-accuracy determination of the neutron flux at n_TOF. THE EUROPEAN PHYSICAL JOURNAL. A, HADRONS AND NUCLEI, 49, 1-11 [10.1140/epja/i2013-13156-x].