紧密脉冲星对通过引力波背景观测暗物质亚结构
Close Pulsar Pairs See Dark Matter Substructure through the Gravitational-Wave Background
- California Institute of Technology（加州理工学院）
- University of California, Berkeley（加州大学伯克利分校）
- University of California, San Diego（加州大学圣地亚哥分校）
- Karlsruhe Institute of Technology (KIT)（卡尔斯鲁厄理工学院）
机构由 AI 辅助整理，请以论文原文为准。
AI总结：
本文提出利用亚秒差距间距的脉冲星对抑制引力波背景噪声，从而显著提升对暗物质亚结构的探测灵敏度，并指出球状星团可提供此类脉冲星对。
AI中文摘要：
脉冲星计时阵列能够探测来自暗物质亚结构的信号，但纳赫兹引力波背景（GWB）会严重降低其灵敏度。我们证明，间隔亚秒差距距离的计时脉冲星对可以避免这种退化。GWB在两个脉冲星上几乎留下相同的扰动，并在其残差之差中被抑制，而附近的暗物质亚晕则对两颗脉冲星产生不同的扰动并得以保留。我们发现，一个包含间隔为0.1秒差距的脉冲星对的阵列，相对于其他方面相同但脉冲星广泛分离的阵列，对约10^-6太阳质量量级的亚晕的灵敏度提高了一个数量级以上。密集的球状星团自然拥有许多这样的脉冲星对，但必须将重子环境与暗物质亚结构信号区分开来。
英文摘要：
Pulsar timing arrays detect signals from dark matter substructure, but a nanohertz gravitational-wave background (GWB) severely degrades their sensitivity. We show that timing pulsar pairs separated by sub-parsec distances avoids this degradation. The GWB imprints nearly the same perturbation on both pulsars and is suppressed in the difference of their residuals, whereas a nearby dark matter subhalo perturbs the two differently and survives. We find that an array with pulsar pairs separated by $0.1\,\mathrm{pc}$ improves the sensitivity to subhalos of order $\sim10^{-6}$ solar masses by more than an order of magnitude, relative to an otherwise identical array of widely separated pulsars. Dense globular clusters naturally host many such pairs, though the baryonic environment must be separated from a dark matter substructure signal.
