Measurement of the 235U(n,f) cross section relative to the 6Li(n,t) and 10B(n,α) standards from thermal to 170 keV neutron energy range at n_TOF

The 235U(n,f) cross section was measured in a wide energy range at n_TOF relative to 6Li(n,t) and 10B(n,α), 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÷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÷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÷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.

AMADUCCI S.;  COSENTINO Luigi;  BARBAGALLO M.;  COLONNA N.;  MENGONI A.;  MASSIMI C.;  LO MEO S.;  FINOCCHIARO Paolo;  ABERLE O.;  ANDRZEJEWSKI J.;  AUDOUIN L.;  BACAK M.;  BALIBREA J.;  BECVÁR F.;  BERTHOUMIEUX E.;  BILLOWES J.;  BOSNAR D.;  BROWN A.;  CAAMANO M.;  CALVIÑO F.;  CALVIANI M.;  CANO-OTT D.;  CARDELLA R.;  CASANOVAS A.;  CERUTTI F.;  CHEN Y. H.;  CHIAVERI E.;  CORTES G.;  CORTES-GIRALDO M. A.;  DAMONE L.;  DIAKAKI M.;  DOMINGO-PARDO C.;  DRESSLER R.;  DUPONT E.;  DURAN I.;  FERNANDEZ-DOMINGUEZ B.;  FERRARI A.;  FERREIRA P.;  FURMAN V.;  GÖBEL K.;  GARCIA A. R.;  GAWLIK A.;  GILARDONI S.;  GLODARIU T.;  GONCALVES I.;  GONZALEZ-ROMERO E.;  GRIESMAYER E.;  GUERRERO C;  GUNSING F.;  HARADA H.;  HEINITZ S.;  HEYSE Jan;  JENKINS D. G.;  JERICHA E.;  KAEPPELER F.;  KADI Y.;  KALAMARA A.;  KAVRIGIN P.;  KIMURA A.;  KIVEL Niko;  KNAPOVA I.;  KOKKORIS M.;  KRTIČKA M.;  KURTULGIL D.;  LEAL-CIDONCHA E.;  LEDERER-WOODS Claudia;  LEEB H.;  LERENDEGUI-MARCO J.;  LONSDALE S.;  MACINA D.;  MANNA A.;  MARGANIEC J.;  MARTÍNEZ T.;  MASI A.;  MASTINU P.;  MASTROMARCO M.;  MAUGERI E.;  MAZZONE A.;  MENDOZA E.;  MILAZZO P. M.;  MINGRONE F.;  MUSUMARRA A.;  NEGRET A.;  NOLTE R.;  OPREA A.;  PATRONIS N.;  PAVLIK Andreas;  PERKOWSKI J.;  PORRAS I.;  PRAENA J.;  QUESADA J.;  RADECK D.;  RAUSCHER T.;  REIFARTH R.;  RUBBIA C.;  RYAN J.;  SABATE-GILARTE M;  SAXENA A.;  SCHILLEBEECKX Peter;  SCHUMANN D.;  SEDYSHEV P.;  SMITH A. G.;  SOSNIN N. V.;  STAMATOPOULOS A.;  TAGLIENTE G.;  TAIN J. L.;  TARIFENO-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. J.;  ZUGEC P.; 

2019-09-02

SPRINGER

JRC115961

1434-6001 (online),   

https://publications.jrc.ec.europa.eu/repository/handle/JRC115961,   

10.1140/epja/i2019-12802-7 (online),