To improve the reliability of the ASDEX pressure gauges in the plasma vessel of the Wendelstein 7-X stellarator, nine of them were equipped with a LaB6 crystal electron emitter for the first time. These crystal cathode pressure gauges were operated during the last campaign in 2018 (operation phase 1.2b) with only 2 A heating current for over 40 h in a magnetic field of about 2.1 T without failure. Owing to this excellent performance, we have decided to equip all pressure gauges with crystal cathodes for the next campaign of Wendelstein 7-X (operation phase 2). We report on a pretest in a superconducting magnet, show a measurement of the neutral pressure in Wendelstein 7-X, and demonstrate the long-term stability of the crystal cathode pressure gauges.

中文翻译：

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用于 Wendelstein 7-X 仿星器中长脉冲操作的新型晶体阴极压力表的性能

为了提高 Wendelstein 7-X 仿星器等离子体容器中 ASDEX 压力计的可靠性，其中 9 台首次配备了 LaB6 晶体电子发射器。这些晶体阴极压力表在 2018 年的最后一次活动（运行阶段 1.2b）中仅使用 2 A 加热电流在约 2.1 T 的磁场中运行超过 40 小时，没有出现故障。由于这种出色的性能，我们决定为 Wendelstein 7-X 的下一个活动（操作阶段 2）为所有压力表配备晶体阴极。我们报告了超导磁体中的预测试，展示了 Wendelstein 7-X 中性压力的测量结果，并证明了晶体阴极压力计的长期稳定性。