Eur. Phys. J. A (2020) 56: 48
https://doi.org/10.1140/epja/s10050-020-00037-8

Review

The fission experimental programme at the CERN n_TOF facility: status and perspectives

¹ Istituto Nazionale di Fisica Nucleare (INFN), Sez. di Bari, Bari, Italy
² European Organisation for Nuclear Research (CERN), Geneva, Switzerland
³ National Technical University of Athens, Athens, Greece
⁴ University of Ioannina, Ioannina, Greece
⁵ CEA, DEN, DER/SPRC/LEPh, Cadarache, 13108, Saint Paul Lez Durance, France
⁶ INFN Laboratori Nazionali del Sud, Catania, Italy
⁷ University of Manchester, Manchester, United Kingdom
⁸ CEA Saclay, Irfu, Université Paris-Saclay, Gif-sur-Yvette, France
⁹ Istituto Nazionale di Astrofisica (INAF), Osservatorio Astronomico di Teramo, Teramo, Italy
¹⁰ Istituto Nazionale di Fisica Nucleare (INFN), Sez. di Perugia, Perugia, Italy
¹¹ European Commission, Joint Research Centre, Directorate G, Retieseweg 111, 2440, Geel, Belgium
¹² Dipartimento di Fisica e Astronomia, Università di Bologna, Bologna, Italy
¹³ Istituto Nazionale di Fisica Nucleare (INFN), Sez. di Bologna, Bologna, Italy
¹⁴ Centro de Investigaciones Energéticas Medioambientales y Tecnológicas (CIEMAT), Madrid, Spain
¹⁵ Horia Hulubei National Institute of Physics and Nuclear Engineering (IFIN-HH), Bucharest, Romania
¹⁶ Physikalisch-Technische Bundesanstalt (PTB), Bundesallee 100, 38116, Braunschweig, Germany
¹⁷ Universidad de Sevilla, Sevilla, Spain
¹⁸ Uppsala University, Uppsala, Sweden
¹⁹ Centre National de la Recherche Scientifique, IN2P3-IPN, Orsay, France
²⁰ Gran Sasso Science Institute (GSSI), L’Aquila, Italy
²¹ Department of Physics, Faculty of Science, University of Zagreb, Zagreb, Croatia

^* e-mail: nicola.colonna@ba.infn.it

Received: 24 June 2019
Accepted: 4 November 2019
Published online: 7 February 2020

Abstract

Neutron-induced fission reactions play a crucial role in a variety of fields of fundamental and applied nuclear science. In basic nuclear physics they provide important information on properties of nuclear matter, while in nuclear technology they are at the basis of present and future reactor designs. Finally, there is a renewed interest in fission reactions in nuclear astrophysics due to the multi-messenger observation of neutron star mergers and the important role played by fission recycling in r-process nucleosynthesis. Although studied for several decades, many fundamental questions still remain on fission reactions, while modern applications and the development of more reliable nuclear models require high-accuracy and consistent experimental data on fission cross sections and other fission observables. To address these needs, an extensive fission research programme has been carried out at the n_TOF neutron time-of-flight facility at CERN during the last 18 years, taking advantage of the high energy resolution, high luminosity and wide energy range of the neutron beam, as well as of the detection and data acquisition systems designed for this purpose. While long-lived isotopes are studied on the 185 m long flight-path, the recent construction of a second experimental area at a distance of about 19 m has opened the way to challenging measurements of short-lived actinides. This article provides an overview of the n_TOF experimental programme on neutron-induced fission reactions along with the main characteristics of the facility, the various detection systems and data analysis techniques used. The most important results on several major and minor actinides obtained so far and the future perspectives of fission measurements at n_TOF are presented and discussed.