We report on the detection of source noise in the time domain at 162 MHz with the Murchison Widefield Array. During the observation, the flux of our target source Virgo A (M87) contributes only $\sim$ 1% to the total power detected by any single antenna; thus, this source noise detection is made in an intermediate regime, where the source flux detected by the entire array is comparable with the noise from a single antenna. The magnitude of source noise detected is precisely in line with predictions. We consider the implications of source noise in this moderately strong regime on observations with current and future instruments.

中文翻译：

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低频源噪声的测量：对现代干涉仪的影响

我们报告了使用 Murchison 宽场阵列在 162 MHz 时域中检测源噪声的情况。在观察过程中，我们的目标源 Virgo A (M87) 的通量只贡献了 $\sim$ 任何单个天线检测到的总功率的 1%；因此，这种源噪声检测是在中间状态下进行的，其中整个阵列检测到的源通量与单个天线的噪声相当。检测到的源噪声幅度与预测完全一致。我们考虑了在这种中等强度的机制中源噪声对当前和未来仪器观测的影响。