We report the results of measurements of the total hemispherical emissivity coefficients of the most popular vacuum compatible materials used in designs of optical atomic clocks. The experimental vacuum test chamber was designed to precisely quantify the heat transfer between material's samples and a calibrated plate that serves as a thermometer. The temperatures of vacuum chamber's internal surfaces were measured and their heat balance equations were solved to designate their emissivities. The simplicity of the experimental set-up allows for analytical calculations of all necessary parameters without use of numerical finite elements methods (FEM). The reported results cover the temperature range between $0.0$ and $25.0^{\circ}$C, that is crucial in optical clocks set-ups operating at room temperatures. The linear model of the emissivity change with the temperature is applied to the measured data to make them applicable in further calculations or FEM simulations.

中文翻译：

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真空兼容材料的发射率：在室温下尽量减少光学原子钟中黑体辐射漂移的不确定性

我们报告了光学原子钟设计中使用的最流行的真空兼容材料的总半球发射系数的测量结果。实验真空测试室旨在精确量化材料样品和用作温度计的校准板之间的热传递。测量真空室内表面的温度并求解它们的热平衡方程以指定它们的发射率。实验设置的简单性允许在不使用数值有限元方法 (FEM) 的情况下对所有必要参数进行分析计算。报告的结果涵盖了 $0.0$ 和 $25.0^{\circ}$C 之间的温度范围，这对于在室温下运行的光学时钟设置至关重要。