The n_TOF facility: Neutron beams for challenging future measurements at CERN

E Chiaveri,F Bečvář,J Andrzejewski,V Variale,F Calviño,L Audouin,N Patronis,T Glodariu,A Pavlik,O Aberle,J Perkowski,M Caamaño,D Radeck,A Tsinganis,Y Kadi,R Vlastou,A Gawlik,A Stamatopoulos,F Gunsing,A Oprea,E Mendoza,J Billowes,M Kokkoris,E Berthoumieux,M Mastromarco,M Krtička,A Casanovas,E Dupont,C Lederer,E Griesmayer,D Macina,E Leal-Cidoncha,F Mingrone,A Kalamara,E Jericha,S Lo Meo,J Lerendegui-Marco,F Käppeler,M Sabaté-Gilarte,A Musumarra,G Tagliente,J Marganiec,R Cardella,A Masi,P Vaz,G Vannini,P Kavrigin,C Rubbia,H Leeb,S Valenta,S Heinitz,M Bacak,T Wright,I Porras,D Schumann,S Warren,C Massimi,B Fernández–Domínguez ,V Vlachoudis,T Rauscher,A Ventura,N V Sosnin ,J Balibrea,S Gilardoni,D Bosnar,L Coséntino ,Paulo Ricardo Araújo Ferreira ,A Tarifeño-Saldivia,P Finocchiaro,J M Quesada ,L A Damone ,A Ferrari,M A Cortés‐Giraldo ,Hideo Harada ,C Domingo‐Pardo ,L Tassan‐Got ,G Cortés,E A Maugeri ,Roeland J M Nolte ,Enrique González ,C Guerrero,A Mengoni,A R García ,J Praena,T Martínez,J A Ryan ,K Göbel,J Heyse,D Cano‐Ott ,R Reifarth,J L Taín ,A Saxena,A Brown,F Cerutti,A Mazzone,I F Gonçalves ,N Colonna,M Calviani,P M Milazzo ,N Kivel,P Mastinu,P J Woods ,A Wallner,D Kurtulgil,Μ Diakaki ,P Schillebeeckx,R Dressler,I Durán,Y H Chen ,P Žugec,A Kimura,S J Lonsdale ,M Barbagallo,A G Smith ,D G Jenkins ,A Negreţ

doi:10.1051/epjconf/201714603001

Abstract

The CERN n_TOF neutron beam facility is characterized by a very high instantaneous neutron flux, excellent TOF resolution at the 185 m long flight path (EAR-1), low intrinsic background and coverage of a wide range of neutron energies, from thermal to a few GeV. These characteristics provide a unique possibility to perform high-accuracy measurements of neutron-induced reaction cross-sections and angular distributions of interest for fundamental and applied Nuclear Physics. Since 2001, the n_TOF Collaboration has collected a wealth of high quality nuclear data relevant for nuclear astrophysics, nuclear reactor technology, nuclear medicine, etc. The overall efficiency of the experimental program and the range of possible measurements has been expanded with the construction of a second experimental area (EAR-2), located 20 m on the vertical of the n_TOF spallation target. This upgrade, which benefits from a neutron flux 30 times higher than in EAR-1, provides a substantial extension in measurement capabilities, opening the possibility to collect data on neutron cross-section of isotopes with short half-lives or available in very small amounts. This contribution will outline the main characteristics of the n_TOF facility, with special emphasis on the new experimental area. In particular, we will discuss the innovative features of the EAR-2 neutron beam that make possible to perform very challenging measurements on short-lived radioisotopes or sub-mg samples, out of reach up to now at other neutron facilities around the world. Finally, the future perspectives of the facility will be presented.

Highlights

The neutron time-of-flight facility n TOF at CERN [1, 2] is a pulsed white neutron source for high-accuracy neutron cross-section measurements over a wide neutron energy range
Since 2001, the n TOF Collaboration has collected a wealth of high quality nuclear data relevant for nuclear astrophysics, nuclear reactor technology, nuclear medicine, etc
We will discuss the innovative features of the experimental areas (EAR)-2 neutron beam that make possible to perform very challenging measurements on short-lived radioisotopes or sub-mg samples, out of reach up to now at other neutron facilities around the world

Summary

Introduction

The neutron time-of-flight facility n TOF at CERN [1, 2] is a pulsed white neutron source for high-accuracy neutron cross-section measurements over a wide neutron energy range. Since the spallation target is placed underground at approximately 20 m under the surface, a very convenient solution was to build the new experimental area just on top of the pit hosting the target, in the vertical direction. With these goals in mind, the construction of the second beam-line started at the beginning of a long accelerator shut-down at CERN, in December 2012, and was completed, with almost perfect timing, before the restart of the PS accelerator, in July 2014

EAR-2 neutron flux

Two measurements demonstrating the performance of EAR-2

Findings

Conclusions