Interaction of a liquid gallium jet with the tokamak ISTTOK edge plasma

Hydrogen retention in gallium samples exposed to ISTTOK plasmas

“…The incidence of protons with ion energies in the 30-40 eV range causes by itself hydrogen enrichment in the 0-5 nm depth range [7]. Differences in retention yield and depth behaviour depends on both the radial hydrogen flux [8,9] and temperature profiles of sample surfaces when exposed to ISTTOK plasmas [4,10]. Hydrogen content values and corresponding retained fractions (H retained /H incident ) are summarised in Table 1.…”

“…The main advantages of gallium are a very high liquid state temperature range and a low chemical reactivity. In a previous work it has been reported that ISTTOK could be operated in the presence of a liquid gallium jet without noticeable discharge degradation, severe effect on the plasma parameters or significant plasma contamination by liquid metal [4].…”

Liquid gallium jet–plasma interaction studies in ISTTOK tokamak

“…In this measurement the observation was done along a viewing line tangent to the plasma, in the equatorial plane and directed towards the jet position. This diagnostic was able to provide additional information on the gallium and gallium ion species spatial distribution inside the plasma [7]. Fig.…”

“…A detailed description of the liquid metal loop installed on IST-TOK to inject gallium at the plasma edge has been done in [7]. Fig.…”

Mass‐Sensitive Ion Probe for Plasma Boundary Characterization on the Tokamak ISTTOK

“…The list of these most probable impurities is presented in Table 1 with indication of the respective ionization potentials for the charge states II, III and IV (the higher charge states are less probable due to low electron temperature of the ISTTOK plasma). The expected sources of these impurities are: (i) carbon sections of the limiter for C; ii) water absorbed on vessel wall for O; (iii) stainless still limiter support ring and tokamak vessel for Cr, Fe, Ni; (iv) droplets survived after operation with liquid gallium limiter [10] for Ga. The results of recalculations are imposed on the experimental data in the same Fig.3 and show a quite good accordance (Fe ions are not shown in the figure being between Cr and Ni ions).…”