Langmuir I. // Proceedings of the National Academy of Sciences of the USA (Proc. <...> Hiden ESPION Advanced Langmuir Probe System: http://www.hidenanalytical.com (Hiden Analytical Ltd.) 12. <...> Godyak V. A., Raitses Y., Fisch N. J.// In: Proc. 30th International Electric Propulsion Conference, Florence, Italy, September 2007. <...> About adequacy of probe diagnostics in RF plasmas V. A. Riaby, V. A. Obukhov RIAME MAI 5 Leningrad rd., Moscow, 125080, Russia E-mail: riame@sokol.ru Problems of probe diagnostics in radio frequency (RF) gas discharge plasma have been considered focusing on the ways and correctness criteria of their solution. <...> It has been found out that presently the art of this diagnostics method has achieved high degree of reliability and sophistication. <...> Objectivity of its results has been established through comparison of joint measurements of electron energy distribution functions using Langmuir probe and spectral line-ratio methods in the same RF plasma experiments. <...> Mutual agreement of the obtained results had been assumed as an evidence for objectivity of both plasma diagnostics methods. <...> PACS: 52.70.Ds/Kz Keywords: gas DC discharge plasma, Q-machine (Q-device), RF discharge, Langmuir probe, Volt-Ampere characteristic, electron energy distribution function. <...>