Henri Navelet (b. October 28, 1938), a former student at the École Normale Supérieure (rue d'Ulm, Paris) and a specialist in strong interactions, was a leading member of the Service de Physique Théorique (now Institut de Physique Théorique) of CEA Saclay since its creation, in 1963.

Henri stood out for his theoretical rigor and remarkable computational skills, which meant a great deal to his collaborators, which include: A. Billoire, G Cohen-Tannoudji, P. J. O' Donnell, J.S. Geronimo, A. Gervois, R. Grigjanis, R. Lacaze, J.C. Le Guillou, A.H. Mueller, A. Morel, R. Peschanski, Ch Royon, M. Sutherland, S. Wallon, and many others.

In the sixties, Henri was a member of the famous "CoMoNav" trio with two other SPhT researchers, Gilles Cohen-Tannoudji and André Morel (deceased in 2013). They were famous in particular for introducing the so-called Regge pole absorption model into the phenomenology of high-energy (at the time!) strong interactions. This model was used by many physicists to untangle the multitude of reactions studied at CERN.

Other Henri's contributions are also very noteworthy, such as his work with Al H. Mueller on very high-energy particle jets, today commonly referred to as "Mueller-Navelet jets", which are still the subject of experimental research and theoretical calculations in Quantum ChromoDynamics.

Henri had a great sense of humor, and human qualities that were highly motivating for his colleagues and the young researchers who met him during his long career. He was not only a great theoretical physicist, but also a passionate sportsman, training the younger generations. In particular, he ran the Marathon in 2h59mn59s!

A valued researcher and friend has passed away.

His friends and colleagues at the Institut de Physique Théorique de Saclay (CEA and UMR CNRS), France