Abstract
In this work, the advantages are presented and discussed of the first-derivative probe technique over the three- and the four-parameter conventional probe techniques for diagnostics of fusion plasmas. The conventional probe techniques for estimation of the plasma potential and the electron temperature and density can only be used when the electron energy distribution function (EEDF) is Maxwellian. The first-derivative probe technique can provide reliable results for the plasma potential and the real EEDF when the latter deviates from Maxwellian. To exemplify the application of the results obtained by different techniques, results on the parallel power-flux density distribution in the divertor region of the COMPASS tokamak, IPP.CR, are presented and discussed.