Photon Acceleration and Its Mechanisms Induced in Plasma by Intense Microwave

强微波等离子体中光子加速及其机制

• 批准号: 08458106
• 负责人: NISHIDA Yasushi
• 金额: $ 5.57万
• 依托单位: Utsunomiya University
• 依托单位国家: 日本
• 项目类别: Grant-in-Aid for Scientific Research (B)
• 财政年份: 1996
• 资助国家: 日本
• 起止时间: 1996 至 1997
• 项目状态: 已结题
• 来源: https://kaken.nii.ac.jp/grant/KAKENHI-PROJECT-08458106/
• 关键词: photon acceleration; laser wakefield; blue shift; frequency up-shift; ponderomotive force; plasma accelerator; intense microwave; microwave plasma interaction; プラズマ利用加速器; プラズマ航跡場; ポンデラモ-ティブ力; プラズマダクト; 電子加速; 非線形効果

The task of this project is to clarify the mechanism of the blue-shift or photon acceleration induced in the frequency of electromagnetic wave irradiated to the plasma. This phenomenon was observed originally in our Laboratory in the investigations related to the laser wakefield acceleration which is simulated by the intense microwavw irradiation to the plasma instead of high power, short pulse laser.In the present works, we have observed specifically two kinds of phenomena, the one is followed by ionization induced by a strong microwave and the other is the phenomena observed in the situation where there is no or almost no ionization. In the second case, the strong standing wave existing within the chamber push to move the plasma by a ponderomotive force to create a blue-shift. The Key differences between two cases are that the upper side-band daughter waves with frequencies such as 6-20 MHz have seen clearly observed when there is no ionization. If the ionization are accompanied, these daughter frequency components are not clear, rather broad band spectrums are observed. As an application of the ptesent phenomena, we have shown the possibilities of DC-AC Radiation Conversion (DARC) phenomenon. This is a direct radiation process of ultra-short pulse microwaves from electrostatic fields.

本课题的任务是阐明电磁波辐照等离子体后，其频率发生蓝移或光子加速的机理。这一现象最初是在我们实验室用强微波辐照等离子体模拟激光韦克菲尔德加速的研究中观察到的，在本工作中，我们具体观察到两种现象，一种是由强微波引起的电离，另一种是在没有或几乎没有电离的情况下观察到的现象。在第二种情况下，存在于腔室中的强驻波通过有质动力推动等离子体移动，从而产生蓝移。两种情况的主要区别在于，当没有电离时，可以清楚地观察到频率为6-20 MHz的上边带子波。如果伴有电离，这些子频率分量就不清楚了，而是观察到较宽的谱带。作为上述现象的一个应用，我们指出了DC-AC辐射转换（DARC）现象的可能性。这是静电场对超短脉冲微波的直接辐射过程。

项目成果

N.Yugami et al.: "Experimental Observation of Short MicrowaveGeneration via Relativistic Ionization front Produced by CO2 Laser" Jpn.J.Appl.Phys.37. 688-689 (1998)

N.Yugami 等人：“通过 CO2 激光产生的相对论电离前沿对短微波发生的实验观察”Jpn.J.Appl.Phys.37。

Rui Zhang et al.: "New Electrodeless Light Source Intensified by Electron Cyclotron Resonance Heating" Jpn.J.Appl.Phys.37. 349-352 (1998)

Rui Zhang 等人：“通过电子回旋共振加热增强的新型无电极光源”Jpn.J.Appl.Phys.37。

H.Ito et al.: "Formation of Plasma Waveguide and Ducting of High Power Microwave in Plasma" J.Plasma and Fusion Res.74(in press). (1998)

H.Ito 等人：“等离子体波导的形成和等离子体中高功率微波的输送”J.Plasma and Fusion Res.74（印刷中）。

H.Ito et al.: "Formation of Plasma Waveguide and Ducting of High Power Microwave in Plasma" J.Plasma and Fusion Research(in print). (1998)

H.Ito 等人：“等离子体波导的形成和等离子体中高功率微波的输送”J.Plasma and Fusion Research（印刷版）。

X.Xu, Y.Nishida and N.Yugami: "Frequency Up-Shift in the Interaction of High Power Microwave with Underdense Inhomogeneous Plasma" J.Plasma and Fusion Research. 72. 91-102 (1996)

X.Xu、Y.Nishida 和 N.Yugami：“高功率微波与低密度非均匀等离子体相互作用中的频率上移”J.等离子体与聚变研究。