AI 中文总结
本文针对由两个同心薄壳组成的致密天体，研究其线性扰动与引力波回声，提出双壳模型，发现谱峰排队现象，表明引力波回声可用于探测致密天体内部结构。
AI 中文摘要
分层是天体的普遍特征。鉴于在与外部固定位置探测器时钟同步的时间概念下，物理黑洞会保留其前身恒星的分层结构这一事实，我们研究由两个同心薄壳组成的致密天体的线性扰动与引力波（GW）回声。与单壳情况相比，双壳结构在有效势中引入了额外势垒，将波传播空间划分为四个耦合有效腔。随着内壳质量比增大，回声谱的高频侧会出现新的谱峰；第二个及后续峰向高频移动；最低频峰先向低频移动，再回到q=0时的位置，我们将这种变化模式称为谱峰排队（SQ）。其存在表明，引力波回声可作为探测所研究致密天体内部结构的探针。
英文摘要
Layering is a ubiquitous feature of astrophysical objects. Motivated by the fact that physical black holes retain the layered structure of their progenitor stars when viewed in the time concepts synchronizable with the clock of an outside fixed-position probe, we investigate linear perturbations and gravitational-wave (GW) echoes from a compact object composed of two concentric thin shells. Compared with the single-shell case, the double-shell structure introduces an extra barrier in the effective potential and partitions the wave propagation space into four coupled effective cavities. As the mass ratio of the inner shell increases, new spectral peaks enter from the high-frequency side of the echo spectrum; the second and later peaks shift toward higher frequencies; and the lowest-frequency peak first shifts toward lower frequencies and then returns to its $q=0$ position. We call this variation pattern spectral-peak queueing (SQ). Its existence suggests that GW echoes can be used as probes for the internal structure of compact objects under consideration.
Comments12 pages, 9 figures, 3 tables
