The History of 14C Dating at LSCE
The Laboratoire des Sciences du Climat et de l’Environnement (LSCE), formerly known as the Centre des Faibles Radioactivités (CFR), has long been home to one of the world’s enduring radiocarbon dating (¹⁴C) facilities. Its story stretches back to the early 1950s, when a first laboratory was established in Fontenay-aux-Roses, followed by a move to Gif-sur-Yvette under the laboratory code Gsy-. Led by Jean Coursaget, the team carried out pioneering experiments, while parallel work at Saclay (lab code Sa-) was co-directed by Georgette Delibrias and Jacques Labeyrie. With the creation of the CFR, these two groups came together on the CNRS campus at Gif-sur-Yvette under the new laboratory code Gif-. The very first ¹⁴C dates were produced in 1954 on a wood sample from New Caledonia (Gsy-1) and in 1956 on a sarcophagus from the temple of Luxor (Sa-1), soon followed by measurements on the temple of Angkor (Sa-2). These early results were swiftly published as comprehensive data lists (Delibrias et al. 1964; Coursaget and Le Run 1966). The first measurement formally registered under the Gif- code was produced in 1966 as sample no. 315, incorporating earlier analyses performed under the Gsy- and Sa- codes.
The ¹⁴C team operated a conventional β-counting facility at Gif-sur-Yvette until 2008, along with an underground β-counting laboratory at Modane (Savoie) that was active from 1990 to 2000 (Fontugne et al. 2021). In parallel, a 3 MV Tandetron accelerator was acquired from High Voltage Engineering in 1982, paving the way for a second radiocarbon dating facility designated under the GifA- code (Arnold et al. 1987). In 1998, under the supervision of Martine Paterne and shortly after the creation of LSCE, these two units were merged, and over the decades the laboratory gradually shifted toward measurements performed exclusively by accelerator mass spectrometry (AMS).
The β-counting laboratory, which produced the first radiocarbon dates for the Laschamps lava flow, the Lascaux cave, the Neolithic Anatolian tell of Çatalhöyük, a linen strip from the mummy of Ramses II, the ancient Semitic city-state of Mari, and many other remarkable sites, is now recognized for its historical and scientific heritage. Most of its counters and associated electronics have been preserved and are now housed at the Musée du Conservatoire National des Arts et Métiers (CNAM) in Paris.
In 2003, the research group operating the Tandetron was dissolved, leaving only the chemical preparation units in service. This led to a transfer of technology — particularly in the design of preparation lines and in chemical expertise — to the French national radiocarbon measurement facility (LMC14). The LSCE ¹⁴C unit regained its capacity for physical measurements in 2015 with the acquisition of a 200 kV compact accelerator dedicated to radiocarbon dating, a Micro Carbon Dating System (MICADAS; Synal et al. 2007). It was named ECHoMICADAS — for Environnement, Climat et Homme — and also as a nod to the numerous funding requests required to secure the necessary resources, its name serving as a subtle echo. This instrument was acquired in collaboration with BioArch¹ and GEOPS² (Tisnérat-Laborde et al. 2015). Its installation triggered renewed scientific activity and marked a new era for GifA- sample numbers: these are now assigned to sample registration and chemical preparation, while physical measurements are catalogued under ECHo- numbers. In 2018, LSCE relocated from its building in the Gif-sur-Yvette valley to the Saclay Plateau, while retaining the same postal address — a practical detail that allowed the GifA- code for chemical preparation to be preserved.
* Arnold M, Bard E, Maurice P, Duplessy JC. 1987. C-14 dating with the Gif-sur-Yvette Tandetron accelerator: status report. Nuclear Instruments and Methods in Physics Research B 29:635–645.
* Coursaget J, Le Run J. 1966. Gif-Sur-Yvette Natural Radiocarbon Measurements I. Radiocarbon 8:128–141.
* Delibrias G, Guillier MT, Labeyrie J. 1964. Saclay Natural Radiocarbon Measurements I. Radiocarbon 6:233–250.
* Fontugne M., Hatté C., Jaudon M. (2022) Experiements at Modane undergroung laboratory or the swan song of the radiocarbon ß-counting by gas proportional counter. Radiocarbon, 64(3), 607-613.
* Tisnérat-Laborde N, Thil F, Synal H-A, Cersoy S, Hatté C, Gauthier C, Massault M, Michelot J-L, Noret A, Siani G, Tombret O, Vigne J-D, Zazzo A. 2015. ECHoMICADAS: a new compact AMS system to measuring 14C for Environment, Climate and Human Sciences, 22nd International Radiocarbon Conference, Dakar, Senegal. PHYS-O.05.