Pulsar timing arrays (PTAs) are sensitive to oscillations in the gravitational potential along the line-of-sight due to ultralight particle pressure. We calculate the probing power of PTAs for ultralight bosons across all frequencies, from those larger than the inverse observation time to those smaller than the inverse distance to the pulsar. We show that since the signal amplitude grows comparably to the degradation in PTA sensitivity at frequencies smaller than inverse observation time, the discovery potential can be extended towards lower masses by over three decades, maintaining high precision. We demonstrate that, in the mass range eV, existing 15-year PTA data can robustly detect or rule out an ultralight component down to of the total dark matter. Non-detection, together with other bounds in different mass ranges, will imply that ultralight scalar/axion can comprise at most of dark matter in the eV range. With 30 years of observation, current PTAs can extend the reach down to , while next-generation PTAs such as SKA can attain the precision. We generalize and derive predictions for ultralight spin-1 vector (i.e. dark photon) and spin-2 tensor dark components.

中文翻译：

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使用脉冲星定时阵列探测超轻标量、矢量和张量暗物质


脉冲星计时阵列 (PTA) 对超轻粒子压力引起的沿视线的引力势振荡敏感。我们计算了 PTA 在所有频率上对超轻玻色子的探测功率，从大于观测时间反比的频率到小于脉冲星距离反比的频率。我们表明，由于在小于逆观测时间的频率下信号幅度的增长与 PTA 灵敏度的下降相当，因此发现潜力可以向更低的质量扩展三十多年，同时保持高精度。我们证明，在 eV 质量范围内，现有 15 年 PTA 数据可以稳健地检测或排除低至总暗物质的超轻成分。未检测到以及不同质量范围内的其他界限将意味着超轻标量/轴子最多可以包含电子伏特范围内的大部分暗物质。经过 30 年的观察，当前的 PTA 可以将范围扩展到 ，而下一代 PTA（例如 SKA）可以达到精度。我们概括并推导出超轻自旋 1 向量（即暗光子）和自旋 2 张量暗分量的预测。