Analysis of long term samples in Tore Supra

Abstract Long term samples have been installed on the inner wall in Tore Supra to monitor the surface modification of the graphite tiles. Surface analyses have shown a very low metallic impurity concentration (∼ 10 16 at/cm 2 ) dominated by stainless steel compounds. The high deuterium concentration (> 10 18 at/cm 2 ) is due to a codeposition with carbon atoms. Carbon layers of about 1 μm have been measured from which we deduced a carbon recycling coefficient R C = 0.99.