In spaceborne gravitational-wave detectors, the stringent requirements on the magnetic cleanliness of the test masses (TMs) make the development of ground-based characterization techniques of their magnetic properties important. An electrostatically controlled torsion pendulum has been built to measure the magnetic properties of TianQin-like solid TMs. The remanent magnetization $m_r$ and the magnetic susceptibility $\chi$ of TMs can be measured at the level of 1 nA ${\mathrm{m}}^2$ and $8\times {10}^{-7}$, respectively. The precisions of measurements are mainly limited by the mechanical sensitivity of silicon fiber. The experimental results from a solid tungsten TM as an example show that the apparatus provides a feasible way to investigate the bulk effect of a full-size TM for the TianQin mission with enough resolution.

中文翻译：

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使用扭摆的重力级检测千克级测试质量的磁性能的测量

在星载重力波探测器中，对测试质量块（TM）的磁性清洁度的严格要求使得发展其磁性特性的地面表征技术变得很重要。已经建立了一个静电控制的扭摆来测量类似天琴的固体TM的磁性能。剩磁${米}_{\mathrm{[R}}$ 和磁化率 $\chi$ 的TM可以在1 nA的水平上进行测量 ${\mathrm{米}}^2$ 和 $8\times {10}^{-7}$， 分别。测量的精度主要受硅纤维的机械灵敏度的限制。以固态钨TM为例的实验结果表明，该装置提供了一种可行的方法来研究具有足够分辨率的全尺寸TM用于天琴任务的整体效果。