ILE DE FRANCE-GRANDE COURONNE CENTRE DE SACLAY IV. ACCELERATORS AND SYNCHROTONS For experiments in physics, the CEA operated the synchrotron Saturne (INB 48) as well as two other accelerators, the Accélerateur linéaire d’électrons de Saclay (ALS; INB 43)) and the MACSE ( Module Accélerateur à Cavité Supraconductrice pour Electrons). The CEA had planned to shut down the Saturne operation on December 31, 1997. The roof of Building 16, covering the accelerator, collapsed on Dec. 2, 1997. The CEA reinforced the structure of the building in 1999. The removal of the collapsed portions was to be completed by February 2000. The final shut-down operations of Saturne were in process at the end of 1999. In 2000 the evacuation of the collapsed parts was completed, and DSIN announced the final shut down [DSIN 2000]. Final shut-down operations and dismantling were completed in 2004 [ASN 04]. Saturne was removed from the list of Basic Nuclear Installations (INBs) in 2005 [ASN 07]. The ALS ceased operating in 1996. In March 2004, the CEA completed the final shut-down operations and dismantling. All radioactive waste was removed. ALS was removed from the list of INBs in September 2006 [ASN 06 and ASN 04]. In 1991, the MACSE was installed in part of the tunnel of the old ALS, made available by dismantling certain sections of the ALS. In 1997, DSIN authorized continuation of MACSE’s operation [DSIN 97]. In 2000, DSIN authorized the installation and ope ration of an apparatus to study the properties of supercondutcing cavities in the perimeter of the ALS. The CEA, the Institute of Nuclear, Particle Physics (IN2P3) and Cern constructed at Saclay a High Intensity Proton Injector (IPHI) of 10 MeV, 100 mA. It is an accelerator head for hybrid systems, each of which includes a sub-critical reactor, a spallation source, and a proton accelerator (see the chapter on Management of Irradiated Fuel) [CNE 99]. Installation of IHPI in the structure that housed Saturn began in 2003 and was completed in 2007. Tests were performed in 2007 and 2008. A portion of IHPI is to be disassembled, transported to Cern, and integrated into the injector for Linac 4/SPL (Superconducting Proton Linac) [IrfuWeb 08]. In December 2006 the CEA inaugurated a third-generation synchrotron, Soleil.
Electrons are produced and accelerated by a Linac, a linear accelerator about 27
meters long. When they reach a speed
approaching that of light and an energy of 100 million electronvolts (eV), they
enter a small, circular booster accelerator which increases their energy to 2.75
billion eV. The electrons then pass
into a “storage ring, a 354-meter tunnel where a vacuum is maintained.
As they circle the ring, they pass by magnets (310 in all), which modify
their trajectory, causing them to lose some of their energy in the form of spectrums
of light of predetermined wavelength. For
the cyclotron to function, the electrons must maintain their energy level.
When, continuing on their circuit, they pass through a cryomodule, an
electromagnetic wave restores the energy that they have lost.
The twenty-four spectra or lines of light, produced in Soleil, permit
scientists to characterize both organic and inorganic materials.
Soleil is therefore used by physicists, chemists, medical researchers,
and biologists. One specific line will be specially equipped for the examination of
radioactive materials: Mars (Matières
radioactives à soleil). They will
be in the form of tiny samples, and will be inside three confinement barriers.
Starting in 2008, the CEA’s Departmentof Nuclear Energy was to study
materials relating to fourth-generation reactors and, in particular, the aging
of fuel and materials submitted to a flow of neutrons. Researchers
from the CEA’s Dam will conduct research on the aging of certain materials and
on the basic properties of actinides. Studies
conducted in Soleil will complement those that can be carried out in the ESRF at
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