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

强相对论电子束回旋加速器超辐射的实验观测。

• 批准号: 11680480
• 负责人: KAMADA Keiichi
• 金额: $ 2.24万
• 依托单位: Kanzawa University
• 依托单位国家: 日本
• 项目类别: Grant-in-Aid for Scientific Research (C)
• 财政年份: 1999
• 资助国家: 日本
• 起止时间: 1999 至 2000
• 项目状态: 已结题
• 来源: https://kaken.nii.ac.jp/grant/KAKENHI-PROJECT-11680480/
• 关键词: intense relativistic electron beam; autoacceleration; superradiance; high-power millimeter wave source; electron cyclotron maser; 大強度電子ビーム; サイクロトロン放射

An ultrashort pulsed high power electron beam with width of 1 ns and energy of 1.1 MeV was obtained from an intense relativistic electron beam with width of 10 ns and energy of 0.55 MeV using 4-stage autoacceleration.The ultrashort pulsed electron beam with width of 1 ns was injected into a cylindrical waveguide immersed in a uniform magnetic field. Intense radiated microwaves with narrow frequency spectrum were observed when the group velocity of the electromagnetic wave coincided with the beam electron velocity, while, the microwave spectrum with the beam with width of 10 ns showed many surplus peaks. The particle simulation code KARAT also indicated that the beam width affected the radiation spectrum.The length of the drift tubes where the beam electrons interacted with the electromagnetic waves was changes. The output power of the radiated microwave increased exponentially with 1 ns and 10 ns beams. The output power of the microwave from 1 ns beam increased more rapidly than that from 10 ns beam. However, that saturated at the length of 40 cm. After 60 cm propagation, the output power from the 1 ns beam was 10 times larger than that from 10 ns beam.These results suggest that the cyclotron superradiance was observed in the experiment. The dependence of the output power on the beam current should be investigated.

利用宽度为10 ns、能量为0.55 MeV的强相对论电子束，采用四级自加速，获得宽度为1 ns、能量为1.1 MeV的超短脉冲高功率电子束。将宽度为1 ns的超短脉冲电子束注入浸入均匀磁场中的圆柱形波导中。当电磁波的群速度与束流电子速度一致时，可观察到强辐射的窄频谱微波，而束宽为10 ns的微波谱显示出许多剩余峰。粒子模拟程序KARAT也表明束流宽度影响辐射光谱。束流电子与电磁波相互作用的漂移管的长度发生变化。辐射微波的输出功率随着 1 ns 和 10 ns 光束呈指数增加。 1 ns 光束的微波输出功率比 10 ns 光束的微波输出功率增加得更快。然而，当长度达到 40 厘米时就饱和了。传播60 cm后，1 ns光束的输出功率比10 ns光束的输出功率大10倍。这些结果表明，实验中观察到了回旋加速器超辐射。应研究输出功率对束流的依赖性。

项目成果

Keiichi Kamada 他: "Two-stage autoacceleration using decreasing length cavities "IEEE trans.Plasma Sci.. 27巻. 1609-1610 (1999)

Keiichi Kamada 等人：“使用减小长度腔的两级自动加速”IEEE trans.Plasma Sci.. Vol. 27. 1609-1610 (1999)

Daisuke Hasegaura 他: "Generation of an intense electron beam with a sub-nanosecond duration using multi-stage autoacceleration."Jpn.J.Appl.Phys..

Daisuke Hasegaura 等人：“使用多级自动加速产生亚纳秒持续时间的强电子束。”Jpn.J.Appl.Phys..

Daisuke Hasegawa 他: "Four-stage autoacceleration for a sub-nanosecond intense relativistic electron beam"IEEE Trans.Plasma Sci.. 28巻. 1648-1652 (2000)

Daisuke Hasekawa 等人：“亚纳秒强相对论电子束的四级自动加速”IEEE Trans.Plasma Sci.. Vol. 28. 1648-1652 (2000)

K.Kamada, D.Hasegawa, K.Shimizu, R.Ando and M.Masuzaki: "Two-stage autoacceleration using decreasing length cavities"IEEE trans.Plasma Sci.. 27巻 6号. 1609-1610 (1999)

K. Kamada、D. Hasekawa、K. Shimizu、R. Ando 和 M. Masuzaki：“使用递减长度腔的两级自动加速”IEEE trans.. Vol 27 No. 6. 1609-1610 (1999)

Keiichi Kamada 他: "Two-Stage autoacceleration using decreasing length cavities"IEEE Trans.Plasma Sci.. 27巻. 1609-1610 (1999)

Keiichi Kamada 等人：“使用减小长度腔的两级自动加速”IEEE Trans.Plasma Sci.. Vol. 27. 1609-1610 (1999)