Anomalous Bremsstrahlung and Anomalous Cyclotron Emission from Partially Ionized Gases

概要

論文の詳細を見る
The anomalous emission at the electron cyclotron frequency in a partially ionized plasma was measured and studied in the range of radio frequency below 1000Mc/s, which had been observed in the microwave region and reported previously. The anomalous cyclotron emission could be observed only when the detecting frequency was above some critical frequency ω_<crit>. The anomalous emission appeared also at the 2nd cyclotron harmonic. The critical frequency was in the range from 70 to 40Mc/s and was somewhat smaller than the collision frequency of plasma electrons. On the other hand, another anomalous emission (anomalous bremsstrahlung) was observed in the rather weaker external magnetic field when the detecting frequency ω was less than the critical frequency ω_<crit>. The characteristics of both anomalous emissions were very similar and would be explained by the same physical mechanism. Therefore, we proposed the following interpretation : if the anomalous cyclotron emission is resulting from the effect of negative absorption due to the cyclotron radiation, then the anomalous bremsstrahlung can be interpreted as a phenomenon of the negative absorption due to the bremsstrahlung. Moreover, it is reasonable that the anomalous cyclotron emission and the anomalous bremsstrahlung occur at a high frequency region (ω>ω_<crit>) and at a low frequency region (ω<ω_<crit>), respectively.
核融合科学研究所の論文