发表机构
Institute of Theoretical Physics, Chinese Academy of Sciences; School of Physical Sciences, University of Chinese Academy of Sciences; Department of Physics, Yantai University; School of Fundamental Physics and Mathematical Sciences, Hangzhou Institute for Advanced Study, University of Chinese Academy of Sciences（中国科学院理论物理研究所; 中国科学院大学物理科学学院; 烟台大学物理系; 中国科学院大学杭州高等研究院基础科学与技术学院）
机构由 AI 辅助整理，请以论文原文为准。AI 中文总结
研究黑洞外径向振荡薄壳对引力波环衰减的影响，推导匹配条件，发现近壳可增强晚期回声振幅约两个数量级，并识别极向模式合并的例外点。
AI 中文摘要
我们研究了黑洞（BH）外部径向振荡薄壳如何影响引力波环衰减，并从运动世界管上的线性化Israel junction条件推导出极向和轴向扰动的匹配条件。周期性壳运动在散射波中产生Floquet边带。对于远距离壳，该运动对即时环衰减影响甚微，仅轻微修改晚期回声。当壳更靠近黑洞时，一个长寿命壳模式的复制品进入入射频带，使晚期回声振幅增加约两个数量级。我们还识别出一个例外点，其中两个极向模式合并，并找到其二阶极点对晚期波形的贡献。
英文摘要
We study how a radially oscillating thin shell outside a black hole (BH) affects gravitational wave ringdown and derive matching conditions for polar and axial perturbations from the linearized Israel junction conditions on the moving worldtube. Periodic shell motion produces Floquet sidebands in the scattered wave. For a distant shell, the motion has little effect on the prompt ringdown and only weakly modifies the late time echoes. When the shell is closer to the BH, a replica of a long lived shell mode enters the incident frequency band, increasing the late time echo amplitude by roughly two orders of magnitude. We also identify an exceptional point where two polar modes coalesce and find the contribution of its second order pole in the late time waveform.
Comments36 pages, 9 figures
