Experimental Observation of Superradiance from an Automodulated Intense Relativistic Electron Beam.

自调制强相对论电子束超辐射的实验观测。

• 批准号: 13680553
• 负责人: KAMADA Keiichi
• 金额: $ 1.98万
• 依托单位: Kanazawa University
• 依托单位国家: 日本
• 项目类别: Grant-in-Aid for Scientific Research (C)
• 财政年份: 2001
• 资助国家: 日本
• 起止时间: 2001 至 2002
• 项目状态: 已结题
• 来源: https://kaken.nii.ac.jp/grant/KAKENHI-PROJECT-13680553/
• 关键词: intense relativistic electron beam; automodulation; superradiance; high-power millimeter wave source; electron cyclotron maser; coaxial cavity; 自動加速; 大強度電磁波; 電磁波放射

It was observed that the length of a coaxial cavity strongly affects the induced gap voltage and the level of automodulation. For high-frequency automodulation for a beam with slow rise time, a series of coaxial cavities with decreasing lengths named multi-stage automodulation was useful.Highly modulated intense eletron beams with modulated frequency around 1 GHz were obtained by the multi-stage automodulation scheme from an intense electron beam with energy of 500 keV, current of 4 kA, duration of 12 ns and rise time of 6 ns. Criteria for the cavity lengths are proposed. The round trip time for electromagnetic wave of the first cavity must be larger than the 1/3 of the current rise time. The lengths of the following cavities are set to the half stage by stage. The round trip time of the last cavity must be set to the half of the desired modulation period.Trains of pulsed microwaves with period of 2 ns which corresponded to the modulated period of an elctron beam were observed. The radiated microwave frequency was around 17 GHz that was reasonable for cyclotron superradience. These results suggest that the cyclotron superradiance can be repeated with a modulated intense electron beam. The dependence of the output power on the beam current should be investigated.

据观察，同轴腔的长度强烈影响感应间隙电压和自调制水平。对于慢上升时间束流的高频自调制，一系列长度递减的同轴腔（称为多级自调制）是有用的。通过多级自调制方案，从能量为500 keV、电流为4 kA、持续时间为12 ns、上升时间为6 ns的强电子束中获得了调制频率在1 GHz左右的高调制强电子束。提出了空腔长度的标准。第一腔体的电磁波往返时间必须大于电流上升时间的1/3。以下腔体的长度逐级设定为半级。最后一个腔体的往返时间必须设置为所需调制周期的一半。观察到周期为 2 ns 的脉冲微波序列，其对应于电子束的调制周期。辐射微波频率约为 17 GHz，对于回旋加速器超辐射来说是合理的。这些结果表明回旋加速器超辐射可以用调制的强电子束重复。应研究输出功率对束流的依赖性。

项目成果

M.Mori, M.Kamada, T.Nishiguchi, R.Ando, K.Kamada: "Propagation of an intense electron beam through a gap"Proc.14th Int. Conf. High-Power Particle Beams. 223-226 (2002)

M.Mori、M.Kamada、T.Nishiguchi、R​​.Ando、K.Kamada：“强电子束通过间隙的传播”Proc.14th Int。

M.Kamada, R.Ando, N.S.Ginzbag, K.Kamada: "Malti-stage automodulation using decreasing length cavities"IEEE trans.Plasama Sci.. (to be published).

M.Kamada、R.Ando、N.S.Ginzbag、K.Kamada：“使用递减长度腔的 Malti 级自动调制”IEEE trans.Plasama Sci..（待出版）。

Masaki kamada, Michiya Mori, Keiichi Kamada, Ritoku Ando, 他: "Automodulation of an intense relativistic elevtron beam using decreasing length cavities"Research Report NIFS-PROC-50. 42-51 (2001)

Masaki kamada、Michiya Mori、Keiichi Kamada、Ritoku Ando 等人：“使用递减长度腔的强相对论电子束的自动调制”研究报告 NIFS-PROC-50 (2001)。

M. Kamada, R. Ando N. S. Ginzburg and K. Kamada: "Multi-stage automodulation using decreasing length cavities"IEEE trans. Plasma Sci.. vol.31. 297-299 (2003)

M. Kamada、R. Ando N. S. Ginzburg 和 K. Kamada：“使用递减长度腔的多级自动调制”IEEE trans。

M.Kamada, M.Mori, Y.Yamada, R.Ando, N.S.Ginzbug, K.Kamada: "Generation of trains of sub-nanosecond banches by automodulation of IREB passing throug a series of coaxial cavitips"Proc.14th Int.Conf.High-Power Particle Beams. 227-230 (2002)

M.Kamada、M.Mori、Y.Yamada、R.Ando、N.S.Ginzbug、K.Kamada：“通过 IREB 自动调制通过一系列同轴腔尖生成亚纳秒级序列”Proc.14th Int.Conf