Vol.:(0123456789) 1 3 Life Cycle Reliability and Safety Engineering https://doi.org/10.1007/s41872-020-00120-5 ORIGINAL RESEARCH Perspectives on nuclear data for advanced reactor design and analysis Umasankari Kannan 1 Received: 23 December 2019 / Accepted: 5 March 2020 © Society for Reliability and Safety (SRESA) 2020 Abstract Nuclear reaction cross section and other neutron physics data are basic inputs to reactor design and analysis. The physical constants such as reaction cross section and other physical constants are usually generated in labs with neutrons as probes, are then coded and subject to detailed evaluation and qualifcation and fnally are made ready for use for potential reactor applications. The nuclear data measurement requires cutting edge technologies from generation of mono-energetic source of neutrons to developing pure targets and covering the entire range of neutron energies and reaction channels. The evaluated data which are created from a best ft of several experiments are then processed to a reactor-specifc dataset which again is a multi-parametric and required diferent treatment in diferent energy regimes and is also for diferent target isotopes. The life cycle of these physical constants from lab to the user is very large, sometimes spans over a few decades. This feld of nuclear data physics, which entails multi-physics covering the entire gamut from experiments to processing, is an exciting branch of reactor design. This paper attempts to give an overview of the importance of these cross-section data for design studies, safety and operation of reactors. Emphasis is mainly in the condensed nuclear datasets used of design simulations. Advanced reactor designs use newer materials, are optimized for better fuel utilization and are required to model more com- plex phenomenon. All these require that the uncertainties in the basic nuclear data be minimized. The deviations in core parameters due to the variations in basic nuclear cross sections are estimated as sensitivity or uncertainty coefcient, which are then accounted for in the design margins. This paper will cover the various aspects of the nuclear data, i.e., experiments to reactor-specifc data, its use in reactors, the infuence on operational parameters and sensitivity studies. Keywords Nuclear data processing · Neutron spectrum · Multi-grouping · Thorium · AHWR · Sensitivity analysis 1 Introduction The quantitative measure of the nuclear processes is termed as “nuclear physics data” or “nuclear data”. There are four main categories of nuclear data as required by the reactor designer and they are : Nuclear constants: like nuclear masses, nuclear bind- ing energies of nucleons and heavy particles, isotopic abundances Nuclear structure data: Nuclear ground and excited states and their energies and quantum states Nuclear decay data: total and partial half-lives of decay- ing nuclear ground and excited states, and decay branch- ing ratios, energies and intensities and radiations emitted in radioactive decay of nuclei, energy spectra of neutrons emitted in spontaneous fssion of actinides, etc. Nuclear reaction data: which are neutron nuclear reaction data, photonuclear, charged particle and light and heavy ion nuclear reaction data. The scope of nuclear data collections includes all 85 natural elements with 290 stable isotopes and more than 4000 radioactive nuclides. About 300 isotopes have been investigated experimentally but many of the few thousands of these nuclei are unexplored. The databases are expanding by inclusion of nuclear data for nuclides far away from the line of beta stability, obtained by researchers using radioac- tive ion beams and for use in studies of s- and r-processes in astrophysics. It can be seen from Fig. 1 that the generation of nuclear data for potential applications is a huge domain, very demanding and has multifarious requirements (Gane- san 2004). Two major aspects to be noted are that for exotic nuclei, no experimental data are available and there are a * Umasankari Kannan uma_k@barc.gov.in 1 Reactor Physics Design Division, Bhabha Atomic Research Centre, Mumbai, India