Gravitational waves from coalescing neutron stars encode information about nuclear matter at extreme densities, inaccessible by laboratory experiments. The late inspiral is influenced by the presence of tides, which depend on the neutron star equation of state. Neutron star mergers are expected to often produce rapidly rotating remnant neutron stars that emit gravitational waves. These will provide clues to the extremely hot post-merger environment. This signature of nuclear matter in gravitational waves contains most information in the 2–4 kHz frequency band, which is outside of the most sensitive band of current detectors. We present the design concept and science case for a Neutron Star Extreme Matter Observatory (NEMO): a gravitational-wave interferometer optimised to study nuclear physics with merging neutron stars. The concept uses high-circulating laser power, quantum squeezing, and a detector topology specifically designed to achieve the high-frequency sensitivity necessary to probe nuclear matter using gravitational waves. Above 1 kHz, the proposed strain sensitivity is comparable to full third-generation detectors at a fraction of the cost. Such sensitivity changes expected event rates for detection of post-merger remnants from approximately one per few decades with two A+ detectors to a few per year and potentially allow for the first gravitational-wave observations of supernovae, isolated neutron stars, and other exotica.

中文翻译：

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中子星极端物质观测站：全球网络中的千赫波段引力波探测器

来自聚结中子星的引力波以极高的密度编码有关核物质的信息，实验室实验无法获得这些信息。晚期吸气受潮汐存在的影响，潮汐取决于中子星状态方程。预计中子星合并通常会产生快速旋转的残余中子星，这些中子星会发射引力波。这些将为极度火热的并购后环境提供线索。引力波中核物质的这种特征包含 2-4 kHz 频带中的大部分信息，这超出了当前探测器最敏感的频带。我们介绍了中子星极端物质观测站 (NEMO) 的设计理念和科学案例：一种引力波干涉仪，经过优化，可研究合并中子星的核物理。该概念使用高循环激光功率、量子压缩和专门设计用于实现使用引力波探测核物质所需的高频灵敏度的探测器拓扑。在 1 kHz 以上，建议的应变灵敏度与完整的第三代探测器相当，而成本只是其中的一小部分。这种敏感性将检测合并后残余物的预期事件率从使用两个 A+ 探测器的大约每几十年一个变为每年几个，并可能允许对超新星、孤立的中子星和其他外来星进行首次引力波观测。所提出的应变灵敏度可与完整的第三代探测器相媲美，而成本只是其中的一小部分。这种敏感性将检测合并后残余物的预期事件率从使用两个 A+ 探测器的大约每几十年一个变为每年几个，并可能允许对超新星、孤立的中子星和其他外来星进行首次引力波观测。所提出的应变灵敏度可与完整的第三代探测器相媲美，而成本只是其中的一小部分。这种敏感性将检测合并后残余物的预期事件率从使用两个 A+ 探测器的大约每几十年一个变为每年几个，并可能允许对超新星、孤立的中子星和其他外来星进行首次引力波观测。