TY - JOUR AU - Virko, V. F. AU - Slobodyan, V. M. AU - Virko, Yu. V. PY - 2019/01/04 Y2 - 2024/03/28 TI - Coupling of Helicon Antennas to Plasma Near the Electron Cyclotron Resonance JF - Ukrainian Journal of Physics JA - Ukr. J. Phys. VL - 61 IS - 11 SE - Plasmas and gases DO - 10.15407/ujpe61.11.0956 UR - https://ujp.bitp.kiev.ua/index.php/ujp/article/view/2019010 SP - 956 AB - <p>Two inductive antennas, which are usually used for the excitation of a helicon discharge on the wave azimuthal modes m = 1 and m = 0, demonstrate unexpectedly different properties near the electron-cyclotron frequency wce. Though the alternating inductive electric field E produced by the antenna m = 1 is mainly parallel to the external steady magnetic field B0, nevertheless the absorption resonance at the frequency wce accompanied by an increase in the plasma density, takes place. For the m = 0 antenna, where these fields are mutually transverse and where the cyclotron resonance seems certainly must be present, it is absent. But the electron-cyclotron resonance (ECR) appears again provided the B0 field is turned up by the right angle around the same m = 0 antenna.</p> ER -