In space detection of gravitational waves (GWs), the presence of a low-frequency varying magnetic field will generate eddy currents in the test mass, resulting in a varying magnetic moment. This magnetic moment will couple with a constant magnetic field gradient, producing residual acceleration within the frequency band of GW detection, causing the test mass to deviate from the free-falling mode. However, this effect has not yet been studied clearly in the noise budget for TianQin and LISA Pathfinder since the constant DC magnetic susceptibility was applied to quantify the varying magnetic moment. This paper utilizes the parameter of alternating current magnetic susceptibility to define this process, and further analyzes and evaluates the effect. In a general magnetic field environment, the contribution of this effect to TianQin acceleration noise reaches 20% from 0.1 mHz to 3 mHz. The contribution to LISA noise is less than 10% from 10⁻⁴ to 0.1 Hz, and less than 10% below 10⁻⁴ Hz. This effect does not have a potential limit on LISA low-frequency science down to 20 µHz (Armano et al 2018 Phys. Rev. Lett. 120 061101).

中文翻译：

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空间引力波探测中带内涡流效应的估计


在引力波 （GW） 的空间探测中，低频变化磁场的存在将在测试质量中产生涡流，从而产生变化的磁矩。该磁矩将与恒定的磁场梯度耦合，在 GW 检测的频带内产生残余加速度，导致测试质量偏离自由落体模式。然而，由于应用恒定直流磁化率来量化变化的磁矩，因此这种效应尚未在 TianQin 和 LISA Pathfinder 的噪声预算中得到明确研究。本文利用交流磁化率参数来定义这一过程，并进一步分析和评估其影响。在一般磁场环境中，这种效应对天琴加速度噪声的贡献在 0.1 mHz 到 3 mHz 范围内达到 20%。从 ^10-4 Hz 到 0.1 Hz 对 LISA 噪声的贡献小于 10%，在 ^10-4 Hz 以下小于 10%。这种效应对低至 20 μHz 的 LISA 低频科学没有潜在限制（Armano 等人，2018 Phys. Rev. Lett.120 061101）。