S³ (Super Separator Spectrometer) is a device designed for experiments with the very high intensity stable beams of LINAG, the superconducting linear accelerator of GANIL, which will be built in the framework of SPIRAL2. These beams, which will provide in a first phase of SPIRAL2 ions with A/q = 3, can reach intensities exceeding 100pμA for lighter ions - A<40-50 - depending on the final choice of the ECR (Electron Cyclotron Resonance) ion source. These unprecedented intensities open new opportunities in several physics domains, e.g. super-heavy and very-heavy nuclei, spectroscopy at and beyond the dripline, isomers and ground state properties, multi-nucleon transfer and deep-inelastic reactions.

The S³ basic design is composed of a two-stage separator. This device, proposed by Argonne, is based on a Momentum Achromat followed by a Mass Separator : MAMS. The basic principle of this device is to first suppress primary beam by at least 1:1000 by a pre-separator (momentum achromat) and then do further beam suppression and physical energy and mass channel selection by a mass separator. This device will have the capabilities to fulfil most of the requirements described before and is well optimized for direct and symmetric kinematics fusion-evaporation reactions. This device is a next-generation separator built on the principles of the Oak Ridge RMS and the Texas A&M MARS separators.