Claude Détraz was born on 20 March 1938 in Albi, in the south of France. He graduated from the École Normale Supérieure and began his research career at CNRS in 1962, studying atomic nuclei. Détraz then joined the Institut de Physique Nucléaire d’Orsay, founded by Irène and Frédéric Joliot Curie, which has recently been merged with its neighbouring laboratories in Orsay to form the Laboratoire de Physique des 2 Infinis Irène Joliot-Curie (IJCLab).
At CERN’s Proton Synchrotron (PS), in collaboration with Robert Klapisch’s team, he contributed to the discovery of the first evidence of deformation in exotic nuclei at a shell closure. Drawing on these results, he became convinced that the beams at the Grand Accélérateur National d’Ions Lourds (GANIL) laboratory in Caen could also become a unique tool in this field.
As director of GANIL from 1982 to 1990, he launched several research projects on exotic nuclei. The legacy of these projects is still with us today and will continue into the future. Détraz was one of the main founders of NuPECC (the Nuclear Physics European Collaboration Committee) and was its first chair from 1989 to 1992, cementing its position as the main coordinating committee for nuclear physics in Europe.
In 1991 Détraz became a technical adviser in the office of the French minister for research, Hubert Curien. Through his involvement with decision-making bodies at all levels in France, Détraz made a major contribution to ensuring that the LHC project was approved in 1994. For example, he played a key role in Curien’s appointment as president of the CERN Council, a position from which he was able to exert a major influence in the final phases of the decision. As director of IN2P3 at CNRS from 1992 to 1998, he helped to provide the impetus, first with Robert Aymar and then with Catherine Cesarsky of the CEA, to France’s wholehearted participation in the LHC adventure.
Détraz made a major contribution to ensuring that the LHC project was approved in 1994
In 1999 Luciano Maiani, CERN Director-General at that time, appointed Détraz as director of research, jointly with Roger Cashmore, until 2003. This was a period filled with important events for CERN, including the shutdown of LEP, the excavation of new caverns for the LHC and the start of a project to send neutrinos from CERN to the underground laboratory at Gran Sasso, to which Claude contributed substantially.
Throughout his career Détraz promoted and supported interaction between scientific disciplines. As a nuclear physicist he established strong links with particle physics. He was also one of the architects of the emergence of astroparticle physics, and received multiple honours both in France and abroad.
Détraz was a great scientist and a true visionary, who played a major role in nuclear and particle physics in France and Europe. As well as being a brilliant scientist and occupying several high-level positions, Claude was a true “Enlightenment. man” of great culture and finesse. He was a shining light of our generation.