The Super Separator Spectrometer (S3) for the SPIRAL2 facility

A Drouart,H Savajols,J.A Nolen

doi:10.1088/1742-6596/1643/1/012032

Abstract

The Super Separator Spectrometer S3 is, with the NFS (Neutrons For Science) facility, a major experimental system developed for SPIRAL2. It is designed for very low cross section experiments at low (<15MeV/u) energy. It will receive the very high intensity (more than 1pμA) stable ion beams accelerated by the superconducting LINAG accelerator of SPIRAL2. S3 will be notably used for the study of rare nuclei produced by fusion evaporation reactions, such as superheavy elements and neutron-deficient isotopes. Such experiments require a high transmission of the products of interest but also a separation of these nuclei from unwanted species. Hence S3 must have a large acceptance but also a high selection power including physical mass resolution. These properties are reached with the use of seven large aperture superconducting quadrupole triplets which include sextupolar and octupolar corrections in a two - stage separator (momentum achromat followed by a mass spectrometer) that can be coupled to the SIRIUS implantation-decay spectroscopy station or to the REGLIS3 gas cell with laser ionization to provide very pure beams for low energy experiments. S3 is now in the construction phase. We will present the scientific objectives of S3 as well as the current status of the facility and its different elements.

Highlights

The region of superheavy elements (Z≥100), with the ultimate goal of the synthesis of new elements to extend the periodic table of Mendeleev
The project “Fast Ion Slow Ion Collisions” (FISIC) addresses the remaining open question of energy deposition by charged particles in matter that takes place in irradiated materials when the ion stopping power is at its maximum
Detection setups The nuclei transmitted to the final focal plane will be studied using complementary detection methods, like spectroscopy of their decay or by measurements of ground state properties

Summary

Introduction

Detailed studies (decay spectroscopy, mass measurements, etc.) of “lighter” superheavy nuclei will be possible. The goal of FISIC is to study ion-ion interaction (notably charge exchange) at the achromatic point of S3. The obvious requirement of the target is to keep a stable behavior under high primary beams intensity (several particle μA).

Results

Conclusion