A wave-dynamical analysis of the interaction of the ordinary wave propagating perpendicularly to the magnetic field across the electron cyclotron resonance is performed. A sufficient condition for the validity of a WKB approach is obtained, but it is shown that as far as the calculation of wave absorption is concerned, WKB results remain a good approximation, even if this condition is violated.
磁場に垂直に伝播する常波と電子サイクロトロン共鳴との相互作用について、波動力学解析を行う。WKB近似の妥当性に対する十分条件が得られるが、波の吸収の計算に関しては、この条件が満たされない場合でもWKB結果が良い近似を保つことが示される。