After initial tests performed during previous observing runs, a Newtonian calibrator (NCal) system was developed and installed on the Virgo gravitational wave detector for the O4 observing run. This system, which is continuously operated, provides the absolute calibration of Virgo for this run. Its 1-σ uncertainty of 0.17% on the amplitudes of the injected signals is better than that obtained with other calibration techniques like the photon calibrator (PCal). This paper presents this NCal system and details the different sources of uncertainties.

中文翻译：

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用于 O4 观测运行的 Virgo 牛顿校准系统


在之前的观测运行中进行了初步测试后，开发了牛顿校准器 （NCal） 系统，并将其安装在 Virgo 引力波探测器上，用于 O4 观测运行。该系统连续运行，为这次运行提供了 Virgo 的绝对校准。它对注入信号振幅的 1-σ 不确定度为 0.17%，优于使用光子校准器 （PCal） 等其他校准技术获得的不确定性。本文介绍了这种 NCal 系统，并详细介绍了不确定性的不同来源。