A difference was determined between temperature defined by International Temperature Scale (ITS-90) and thermodynamic temperature measured by relative acoustic gas thermometry at 79.0000 K and at 83.8058 K. Measurement were carried out using misaligned spherical acoustic resonator filled with helium at different pressures. The isotherms were fitted for four different acoustic modes simultaneously assuming the same thermal accommodation coefficient and third acoustic virial coefficient for all modes. Our measurements yield the following differences between the thermodynamic temperature T and ITS-90 temperature $$T_{90}$$ T 90 : $$T-T_{90}=-4.81 \pm 1.02$$ T - T 90 = - 4.81 ± 1.02 mK at 83.9058 K and $$T-T_{90}=-4.47 \pm 0.97$$ T - T 90 = - 4.47 ± 0.97 mK at 79.0000 K.

中文翻译：

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由 ITS-90 温标确定的温度与由声学气体温度计在 79.0000 K 和 83.8058 K 下测量的热力学温度的偏差

确定由国际温标 (ITS-90) 定义的温度与通过相对声学气体温度计在 79.0000 K 和 83.8058 K 处测量的热力学温度之间的差异。使用在不同压力下填充氦气的未对准球形声学谐振器进行测量。假设所有模式具有相同的热调节系数和第三声学维里系数，同时拟合四种不同声学模式的等温线。我们的测量得出热力学温度 T 和 ITS-90 温度之间的以下差异 $$T_{90}$$ T 90 ： $$T-T_{90}=-4.81 \pm 1.02$$ T - T 90 = - 4.81 ± 1.02 mK 在 83.9058 K 和 $$T-T_{90}=-4.47 \pm 0.97$$ T - T 90 = - 4.47 ± 0.97 mK 在 79.0000 K。