Eur. Phys. J. A (2021) 57: 210
https://doi.org/10.1140/epja/s10050-021-00486-9

Regular Article - Theoretical Physics

An impact of Jacques Raynal on nuclear data evaluation

¹ NAPC–Nuclear Data Section, International Atomic Energy Agency, 1400, Vienna, Austria
² Departamento de Física Atómica, Molecular y Nuclear, Universidad de Sevilla, Ap.1065, 41080, Sevilla, Spain

^a r.capotenoy@iaea.org

Received: 26 April 2021
Accepted: 7 May 2021
Published online: 28 June 2021

Abstract

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 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.