SYNCHROTRON-RADIATION AND ABSORPTION AT 3-OMEGA(CE) WITH X-MODE O-MODE COUPLING

The mode conversion-tunneling equation with weakly relativistic absorp tion at 3omega(ce) has been solved by using the' Green function method . The numerical results show that the reflection and conversion coeffi cients are dramatically reduced when relativistic absorption is includ ed, while the transmission coefficients and the conversion coefficient from the X-mode on the high field side to the O-mode on the low field side are independent of absorption. The reduction of these coefficien ts leads to the reduction of the asymmetry in the absorption between d ifferent wave branches. The numerical results also show that the relat ivistic effect is important even for a relatively low temperature plas ma. An important relationship between solutions is expressed by the re ciprocity relations which have been proved for any harmonic number. Th ese analyses modify the interpretation of electron cyclotron emission (ECE).