MICROSCOPE is a space mission launched in 2016 that aims to test the validity of the Equivalence Principle (EP), the main postulate of General Relativity (GR), with a precision never reached before (Touboul et al., 2001). EP states that two bodies of different compositions and masses fall with the same acceleration in the same gravitational field. In order to achieve this goal, MICROSCOPE’s instrument is composed of two identical electrostatic differential accelerometers. MICROSCOPE will be the first lab to realize an experiment to test the EP in space which allows to break free from perturbations other than gravity. Those tests used to be presented in terms of the Eötvös ratio $\eta$. The first result published in December 2017 shows no evidence of violation higher than $1.3\times {10}^{-14}$ at 1 $\sigma$ on $\eta$ (Touboul et al., 2017). This result was obtained with only 7% of the whole data, so the statistical uncertainty would be improved with the analysis of the complete data. During the experiment some thermal variations could disturb the estimation of the Eötvös parameter. In order to better estimate the thermal systematic effect, the thermal sensitivity has to be determined. To do so, thermal stimulus are induced on the instrument by means of dedicated heaters and the response in the measured acceleration is analysed. Two methods were applied for theses analysis and will be presented in this paper. The first one operates in the time domain and the second one in the frequency domain. Those methods allow us to obtain a thermal systematic of $8.6\times {10}^{-16}$ which represents an improvement by one order of magnitude with respect to the result of Touboul et al. (2017).

MICROSCOPE 是一项于 2016 年发射的太空任务，旨在以前所未有的精度测试等效原理 (EP)（广义相对论 (GR) 的主要假设）的有效性（Touboul 等人，2001 年）。EP 指出，不同成分和质量的两个物体在同一引力场中以相同的加速度下落。为了实现这一目标，MICROSCOPE 的仪器由两个相同的静电差分加速度计组成。MICROSCOPE 将是第一个实现在太空中测试 EP 的实验的实验室，该实验可以摆脱重力以外的扰动。这些测试过去以 Eötvös 比率表示$\eta$. 2017 年 12 月发布的第一个结果显示，没有证据表明违规行为高于$1.3\times {10}^{——14}$ 在 1 $\sigma$ 上 $\eta$（Touboul 等人，2017 年）。这个结果只用整个数据的 7% 就得到了，所以通过对完整数据的分析，统计的不确定性会得到改善。在实验过程中，一些热变化可能会干扰 Eötvös 参数的估计。为了更好地估计热系统效应，必须确定热灵敏度。为此，通过专用加热器在仪器上产生热刺激，并分析测量加速度的响应。本文采用了两种方法进行分析，并将在本文中进行介绍。第一个在时域中操作，第二个在频域中操作。这些方法使我们能够获得热系统$8.6\times {10}^{——16}$这表示相对于 Touboul 等人的结果提高了一个数量级。(2017)。