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Novel method to measure unloaded quality factor of resonant cavities at room temperature

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Abstract

We demonstrated a novel method to measure the unloaded quality factor (Q factor) of high-Q resonant cavities. This method was used to obtain data with low errors and calculate the unloaded Q factor. This procedure was more reliable than traditional methods. The data required for the method were near the resonant frequency, not at the half-power points of the reflection coefficient curve or Smith chart. We applied the new method to measure a resonant cavity with an unloaded Q factor of ~ 100,000, obtaining good agreement between the measured and theoretical results.

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Authors and Affiliations

  1. Department of Engineering Physics, Tsinghua University, Beijing, 100084, China

    Ping Wang, Jia-Ru Shi, Ze-Ning Liu, Cheng Cheng & Huai-Bi Chen

  2. Key Laboratory of Particle and Radiation Imaging of Ministry of Education, Tsinghua University, Beijing, 100084, China

    Ping Wang, Jia-Ru Shi, Ze-Ning Liu, Cheng Cheng & Huai-Bi Chen

  3. Northwest Institute of Nuclear Technology, Xi’an, 710024, China

    Zheng-Feng Xiong

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  1. Ping Wang
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  2. Jia-Ru Shi
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  3. Zheng-Feng Xiong
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  4. Ze-Ning Liu
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  5. Cheng Cheng
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Corresponding author

Correspondence to Ping Wang.

Additional information

This work was supported by the National Key Research and Development Program of China (No. 2016YFA0401902).

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Wang, P., Shi, JR., Xiong, ZF. et al. Novel method to measure unloaded quality factor of resonant cavities at room temperature. NUCL SCI TECH 29, 50 (2018). https://doi.org/10.1007/s41365-018-0383-3

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