Investigation of carbon transport in the scrape-off layer of TEXTOR-94

13CH4 was injected into 18 consecutive ohmic discharges (108 s) through a hole in a graphite block equipped with an aluminium plate. CH and CII radical emission adjacent the hole was observed by spectroscopy, while the incremental grow of the deposit was measured in situ by colorimetry. SIMS depth profiling yielded the fractions of 13C and of the 12C out of the background. Ratios up to 13C/C≈0.42 were found although the deposition efficiency for 13C was only about 0.2%. H and D were co-deposited up to ratios of 0.4 and 0.2, respectively, as measured by NRA and ERDA. The results can be simulated quantitatively by means of the ERO-TEXTOR code if high re-erosion is assumed for the hydrogen rich radicals CHx+. Within the interaction depth the 13C/C ratio seems to become quasi-stationary. 13C transported to obstacles creates a ratio of 13C/C≈0.27 after 108 s.