@inproceedings{oai:u-fukui.repo.nii.ac.jp:00029018,
 author = {Iwata, Y and Ogawa, I and Idehara, T},
 book = {遠赤外技術に関する国際シンポジウム, Proceedings of 2nd International Workshop on Far Infrared Technologies},
 month = {},
 note = {It is known that the gyration output frequency varies with a long time CW operation. When the condition for the operation is the s~rne as the magnetic field and accelerating voltage, output frequency depends on radials of cavity. Generally, electromagnetic wave in the cavity makes a loss and this energy is changed into thermal. This effect changes cavity size. In this experiment, we measure the relation between output frequency and cavity temperature. In measurement system, ・the output frequency is measured by a heterodyne receiving system.
However, cavity temperature can't be measured directly. So we measure cavity  cooling.water temperature to calculate cavity temperature. As the result of this experiment, when the output power is 4W, the drift of output frequency is 71 MHz and the increase of the water temperature is by 1.3 degrees. And when output power is 8W, drift of output frequency is 119 MHz and the increase of water temperature is by 2.0 degrees. This result shows that the cavity radius and frequency depend on the power of electromagnetic wave at cavity.},
 publisher = {Research Center for Development of Far Infrared Region,Fukui University},
 title = {Frequency shift in a long CW operation of gyrotron},
 volume = {2002},
 year = {2002}
}