It is with deep sadness that we announce the death of our colleague Marc Chemtob, who passed away on August 11, 2026, at the age of 85.Born on December 12, 1940, in Alexandria (Egypt), Marc spent his entire career at the Service de Physique Théorique (predecessor of IPhT) of CEA Saclay.
Marc arrived at CEA as a stagiaire de longue durée (research trainee) on September 17, 1962, first at the Synchrotron Saturne, then, starting November 26, 1962, at the Département des Études de Piles within the Service de Physique Mathématique of Claude Bloch, which became the Service de Physique Théorique in early 1963.
From 1963 to 1969, he worked at the SPhT as a thesis fellow of the Institut National des Sciences et Techniques Nucléaires, under the supervision of V. Gillet, in the field of low-energy nuclear physics. He obtained his Doctorat d’État in 1969.
Marc joined the CNRS in October 1969 and remained there until his retirement in 2007 as a Director of Research, First Class. Among his collaborators at the SPhT were: J.-P. Blaizot, A. Billoire, Ph. Brax, A. Lumbroso, S. Lavignac, H. Navelet, R. Pechanski, and M. Rho. Visits to the Niels Bohr Institute in Copenhagen, Stony Brook, and the Technion in Haifa enriched his scientific and international outlook.
Marc first distinguished himself in low-energy nuclear physics and the study of strong interactions: his work on mesonic exchange currents, particularly those carried out with Mannque Rho on exchange currents in weak and electromagnetic nuclear interactions, remains a reference in the field. His research embraced a great diversity of topics in nuclear and hadronic physics, but also in particle phenomenology, to which he turned in the mid-1990s. He then addressed topics related to physics beyond the Standard Model, supersymmetry (he co-authored an important review on supersymmetry with R-parity violation in this field), and, toward the end of his career, also explored string phenomenology, working on orbifold compactifications with D-branes.
A discreet yet warm person, Marc stayed away from noise and agitation, pursuing his work with perseverance and rare determination. He will remain in memory as a passionate researcher, of great kindness, whose company was always pleasant.
The community loses a physicist of great rigor, whose contributions covered with equal mastery nuclear physics and particle physics. We extend our deepest condolences to his family and loved ones.