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arXiv · 2208.03046

A Gaseous Time Projection Chamber with Micromegas Readout for Low Radioactive Material Screening

Haiyan Du·Chengbo Du·Ke Han·Shengming He·Liqiang Liu·Yue Meng·Shaobo Wang·Tao Zhang·Wenming Zhang·Li Zhao·Jifang Zhou
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Abstract

Low radioactive material screening is becoming essential for rare event search experiments, such as neutrinoless double beta decay and dark matter searches in underground laboratories. A gaseous time projection chamber (TPC) can be used for such purposes with large active areas and high efficiency. A gaseous TPC with a Micromegas readout plane of approximately 20$\times$20 cm$^2$ is successfully constructed for surface alpha contamination measurements. We have characterized the energy resolution, gain stability, and tracking capability with calibration sources. With the unique track-related background suppression cuts of the gaseous TPC, we have established that the alpha background rate of the TPC is 0.13$\pm$0.03 $\mu$Bq/cm$^2$, comparable to the leading commercial solutions.

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Haiyan Du, Chengbo Du, Ke Han, Shengming He, Liqiang Liu, Yue Meng, Shaobo Wang, Tao Zhang, Wenming Zhang, Li Zhao, Jifang Zhou. 2022-08-05. A Gaseous Time Projection Chamber with Micromegas Readout for Low Radioactive Material Screening. https://arxiv.org/abs/2208.03046

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