2000 - 2002
Study on Slow-Wave Cyclotron Maser Based on Anomalous Doppler Effect
Japan Society for the Promotion of Science Grants-in-Aid for Scientific Research Grant-in-Aid for Scientific Research (B) Grant-in-Aid for Scientific Research (B)
- Grant number
- 12480116
- Japan Grant Number (JGN)
- JP12480116
- Grant amount
-
- (Total)
- 14,600,000 Japanese Yen
- (Direct funding)
- 14,600,000 Japanese Yen
In this research, slow-wave cyclotron maser based on the induced radiation at the anomalous Doppler cyclotron frequency has been proposed The outline of this work is summarized.
・Magnetic system and electron beam
Magnetic system has been newly built. The magnetic field configuration is controlled by the current distribution of magnetic coils. And the uniform magnetic field is obtained in the range of the 414mm of the axial direction, and the 60mm of the radial direction. By controlling the magnetic field, the electron beam of about 60kV and several hundreds A is able to propagate over 360mm in a vacuum vessel.
・Slow-wave cyclotron maser based on the anomalous Doppler effect
The theoretical analysis of slow-wave cyclotron maser has been published in Physical Review E as a regular article. K-band microwave generation has been investigated experimentally. Oscillation frequency is in the range of 20 to 25 GHz, and radiation power is about 100kW (about 2%) at the maximum. In a lower magnetic field region, the oscillations in non-axisymmetric mode are observed, which may be attributed to slow-wave cyclotron maser operation based on the anomalous Doppler effect. This shows the possibility of the control of the Cherenkov interaction and the slow-wave cyclotron interaction by a magnetic field.
・Experimental research aiming at higher frequency operation
For higher frequency operation in millimeter wave region, a Q-band large diameter slow-wave structure is manufactured. With this slow-wave structure, the millimeter wave with a frequency of about 35GHz is obtained. Radiation power is about 30kW or less (the oscillation efficiency is about 0.4%) at the maximum, ard is about 1/4 compared with K-band experiments.
Control with the high accuracy of a beam is required for resonance-operation with the slow-wave cyclotron interaction and the Cherenkov interaction, or stabilization operation in a lower magnetic field region. Technology for such control of large current electron beam propagation is a future subject. It is necessary to make theoretical analysis and experiment cooperate and to advance research.
・Magnetic system and electron beam
Magnetic system has been newly built. The magnetic field configuration is controlled by the current distribution of magnetic coils. And the uniform magnetic field is obtained in the range of the 414mm of the axial direction, and the 60mm of the radial direction. By controlling the magnetic field, the electron beam of about 60kV and several hundreds A is able to propagate over 360mm in a vacuum vessel.
・Slow-wave cyclotron maser based on the anomalous Doppler effect
The theoretical analysis of slow-wave cyclotron maser has been published in Physical Review E as a regular article. K-band microwave generation has been investigated experimentally. Oscillation frequency is in the range of 20 to 25 GHz, and radiation power is about 100kW (about 2%) at the maximum. In a lower magnetic field region, the oscillations in non-axisymmetric mode are observed, which may be attributed to slow-wave cyclotron maser operation based on the anomalous Doppler effect. This shows the possibility of the control of the Cherenkov interaction and the slow-wave cyclotron interaction by a magnetic field.
・Experimental research aiming at higher frequency operation
For higher frequency operation in millimeter wave region, a Q-band large diameter slow-wave structure is manufactured. With this slow-wave structure, the millimeter wave with a frequency of about 35GHz is obtained. Radiation power is about 30kW or less (the oscillation efficiency is about 0.4%) at the maximum, ard is about 1/4 compared with K-band experiments.
Control with the high accuracy of a beam is required for resonance-operation with the slow-wave cyclotron interaction and the Cherenkov interaction, or stabilization operation in a lower magnetic field region. Technology for such control of large current electron beam propagation is a future subject. It is necessary to make theoretical analysis and experiment cooperate and to advance research.
- Link information
- ID information
-
- Grant number : 12480116
- Japan Grant Number (JGN) : JP12480116