Design of a High-Gain, High-Efficiency, and Compact Metamaterial-Inspired 648-MHz Klystron for CSNS-II

IF 1.6 4区物理与天体物理 Q3 PHYSICS, FLUIDS & PLASMAS

IEEE Transactions on Plasma Science Pub Date : 2026-10-01 Epub Date: 2026-09-17 DOI:10.1109/TPS.2026.3731994

Chuanchao Wang;Deyong Li;Xuanming Zhang;Hexin Wang;Zhencheng Mu;Shaozhe Wang;Jianjun Zou;Yongming Li;Yubin Gong;Sheng Wang;Zhaoyun Duan

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引用次数: 0

Abstract

A compact metamaterial-inspired 648-MHz klystron for China Spallation Neutron Source second phase (CSNS-II) linac is investigated. By loading all-metal complementary electric split-ring resonators (CeSRRs) on the drift tube of a reentrant cavity, the cavity diameter is reduced to 198 mm, corresponding to

$0.43\lambda $

. To account for the transverse nonuniformity of the cavity fields, area-averaged values of the characteristic impedance and coupling coefficient over the cross section of the electron beam are used in AJDisk. A six-cavity metamaterial-inspired high-frequency structure (MIHFS) with a second harmonic cavity is then optimized. Its cylindrical envelope volume is 40.24% smaller than that of the conventional 648-MHz klystron design. For a beam voltage of 97 kV and a beam current of 19.64 A, 3-D particle-in-cell (PIC) simulations predict an output power of 1.32 MW, an electron efficiency of 69.38%, and a gain of 49.17 dB at an RF drive power of 16 W. Vacuum breakdown risk analysis and multiphysics study predict a peak electric field of 8.58 MV/m and a maximum output cavity temperature of

$43.29~^{\circ }$

C with water cooling. These results indicate that the CeSRR-loaded structure is a feasible route to a compact MW-level 648-MHz klystron.

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用于CSNS-II的高增益、高效率、紧凑型超材料648 mhz速调管设计

研究了用于中国散裂中子源第二相（cssn - ii）直线加速器的紧凑型超材料激励648-MHz速调管。通过在重入腔的漂移管上加载全金属互补电分裂环谐振器（cesrr），将腔直径减小到198 mm，对应于$0.43\lambda $。为了考虑腔场的横向非均匀性，在AJDisk中使用了电子束截面上的特征阻抗和耦合系数的面积平均值。然后对具有二次谐振腔的六腔超材料激发高频结构（MIHFS）进行了优化。其圆柱包络体积比传统的648 mhz速调管设计小40.24%。当束流电压为97 kV，束流电流为19.64 a时，三维粒子池（PIC）模拟结果表明，在16w的射频驱动功率下，输出功率为1.32 MW，电子效率为69.38%，增益为49.17 dB。真空击穿风险分析和多物理场研究预测了水冷时的峰值电场为8.58 MV/m，最大输出腔温为43.29~^{\circ}$ C。这些结果表明，cesrr负载结构是实现紧凑的毫瓦级648-MHz速调管的可行途径。

本文章由计算机程序翻译，如有差异，请以英文原文为准。

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来源期刊

IEEE Transactions on Plasma Science 物理-物理：流体与等离子体

CiteScore

3.00

自引率

20.00%

发文量

538

审稿时长

3.8 months

期刊介绍： The scope covers all aspects of the theory and application of plasma science. It includes the following areas: magnetohydrodynamics; thermionics and plasma diodes; basic plasma phenomena; gaseous electronics; microwave/plasma interaction; electron, ion, and plasma sources; space plasmas; intense electron and ion beams; laser-plasma interactions; plasma diagnostics; plasma chemistry and processing; solid-state plasmas; plasma heating; plasma for controlled fusion research; high energy density plasmas; industrial/commercial applications of plasma physics; plasma waves and instabilities; and high power microwave and submillimeter wave generation.