An impact of Jacques Raynal on nuclear data evaluation

• Published in: The European physical journal. A, Hadrons and nuclei Vol. 57; no. 6
• Main Authors: Capote, R., Quesada, J. M.
• Format: Journal Article
• Language: English
• Published: Berlin/Heidelberg Springer Berlin Heidelberg 01.06.2021; Springer Nature B.V
• Subjects: Compound channels; Decay; Hadrons; Heavy Ions; Inelastic scattering; Nuclear fuels; Nuclear Fusion; Nuclear Physics; Nuclear power reactors; Nuclear Reaction Studies: a Tribute to Jacques Raynal; Nuclear reactor components; Nuclear reactors; Particle and Nuclear Physics; Physics; Physics and Astronomy; Power reactors; Regular Article - Theoretical Physics; Scattering cross sections
• ISSN: 1434-6001; 1434-601X
• DOI: 10.1140/epja/s10050-021-00486-9

Jacques Raynal seminal contributions to the optical model development and numerical implementation of the solution of coupled-channel equations have been key to generate nuclear data for applications in the last three decades. We recall some of the interactions we had with Jacques from late nineties up until his death. His ECIS code was for a long time, since his collaboration with Peter Moldauer in early eighties, the only optical model and compound decay code where Engelbrecht–Weidenmüller transformation was implemented to consider the impact of strongly coupled channels with large direct inelastic cross sections on the decay of the compound channel. Such physical effect, which was neglected for a long time, proved very important to describe the observed enhancement (Relative to the bare Hauser–Feschbach calculation) of the inelastic scattering cross section on 238 U nucleus, which is a major fuel component in nuclear power reactors. Jacques also proposed an unique and very clever method to calculate dispersive integrals analytically in 1996. His excellent mathematical background and programming skills set a very high bar for future generations. This contribution represents a small homage to our dear colleague and friend.