Experimental results from TEXTOR are presented to provide strong evidence for the feasibility of the "cold radiative plasma mantle", a concept which might be a possible solution for the energy exhaust problem in a fusion reactor. The concept is compared with the high density divertor. The compatibility to other constraints, limitations and open problems are discussed, in particular the issues of stationarity (feed-back control, thermal instabilities, q=2), energy confinement. Heexhaust and fuel dilution.

The Doppler broadened profile of a C I line in the infrared (λ =909.5 nm, 3P2 to 3P20) has been measured with high spectral resolution (λ/Δλ > 105) in front of a graphite limiter in the TEXTOR tokamak. The line shows a strong Zeeman effect, but by selecting the pi component with a polarizer, the influence of the magnetic field of TEXTOR on the line shape can be practically eliminated, and the profile is determined only by the velocity distribution of the carbon atoms. By a comparison of shots with a 'detached plasma' and shots with injected gas (CO, CH4) it could be shown that the carbon flux from the limiter is mainly determined by chemical sputtering in a 'detached plasma'. In a plasma attached to the limiter, the energy of the released carbon atoms increases with the electron temperature (Te) at the limiter, the typical width of the line gradually increases from about 16 pm to 50 pm (corresponding to velocities of 5 × 105 to 1.5 × 106 cm/s or energies of 1.5 to 13.5 eV), indicating that physical sputtering dominates at high Te and that chemical sputtering then gives only a small contribution (<15%) to the impurity production at the limiter

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