Nondestructive measurement of surface tritium by beta-ray induced X-ray spectrometry (BIXS)

Applicability of a newly developed beta -ray induced X-ray spectrometry (BI XS) has been examined to measure nondestructively tritium retained on/in th e graphite samples. Examination was carried out by using the graphite plate s irradiated with tritium ions and an ALT-II limiter tile exposed to D-plas mas in TEXTOR. For the former samples, a sharp intense peak and a broad wea k peak appeared clearly in the spectra; the former peak was attributed to t he characteristic X-rays from argon used as a working gas, and the latter p eak was assigned to the bremsstrahlung X-rays from sub-surface layers of gr aphite. On the other hand, for the latter sample, a rather weak characteris tic X-ray peak was observed along with a diminutive bremsstrahlung X-ray pe ak. Although the intensities of those X-rays differed from spot to spot, th e tritium levels retained on the limiter tile were determined to be 58-132 Bq/cm(2). It was concluded, therefore, that valuable information on the amo unt and the distribution of tritium retained on/in the wall materials can b e nondestructively obtained by using the BIXS. (C) 2001 Elsevier Science B. V. All rights reserved.