Diagnostic integration issues in the tore supra upgrade project WEST

The WEST project (W - for tungsten - Environment in Steady-state Tokamak) consists in transforming the French tokamak Tore Supra into an X-point divertor one and aims at testing the ITER technology of actively cooled high heat flux tungsten components during ITER-relevant long pulses. In addition to the integration in the vacuum vessel of a lower divertor and an upper one, this metamorphosis has a strong impact on diagnostics initially present in Tore Supra. Indeed the introduction of a divertor in the upper part of the machine leads to block the lines of sight of diagnostics previously installed in the upper ports. Therefore new diagnostics playing a paramount role for the safe tokamak operation need to be implemented, such as an infrared thermography diagnostic for the protection of plasma-facing components (PFCs) and heating antennas, and a visible spectroscopy system for the protection of tungsten PFCs. Besides several existing diagnostics need to be modified to adapt their lines of sight to the new divertor targets and plasma shape. This paper presents the main issues linked to the integration of diagnostics deriving from the WEST upgrade project. First the changes involved by the upgrade on the set of diagnostics currently implemented in Tore Supra are described. Then a particular focus is put on the integration of the two new optical systems, namely the infrared system and the visible spectroscopy one. These two systems being located within the vacuum vessel, a special care must be paid to their design, to allow them to withstand their harsh environmental conditions. Other new or updated fundamental diagnostics are also briefly presented. Finally the resulting new implementation of diagnostics envisaged to reach the scientific and technological goals of the WEST project is described.