PDF(Pubmed)
Abstract：
Due to the growing capacity of gravitational-wave astronomy and black-hole imaging, we will soon be able to emphatically decide if astrophysical dark objects lurking in galactic centers are black holes. Sgr A*, one of the most prolific astronomical radio sources in our galaxy, is the focal point for tests of general relativity. Current mass and spin constraints predict that the central object of the Milky Way is supermassive and slowly rotating, thus can be conservatively modeled as a Schwarzschild black hole. Nevertheless, the well-established presence of accretion disks and astrophysical environments around supermassive compact objects can significantly deform their geometry and complicate their observational scientific yield. Here, we study extreme-mass-ratio binaries comprised of a minuscule secondary object inspiraling onto a supermassive Zipoy-Voorhees compact object; the simplest exact solution of general relativity that describes a static, spheroidal deformation of Schwarzschild spacetime. We examine geodesics of prolate and oblate deformations for generic orbits and reevaluate the non-integrability of Zipoy-Voorhees spacetime through the existence of resonant islands in the orbital phase space. By including radiation loss with post-Newtonian techniques, we evolve stellar-mass secondary objects around a supermassive Zipoy-Voorhees primary and find clear imprints of non-integrability in these systems. The peculiar structure of the primary, allows for, not only typical single crossings of transient resonant islands, that are well-known for non-Kerr objects, but also inspirals that transverse through several islands, in a brief period of time, that lead to multiple glitches in the gravitational-wave frequency evolution of the binary. The detectability of glitches with future spaceborne detectors can, therefore, narrow down the parameter space of exotic solutions that, otherwise, can cast identical shadows with black holes.
摘要：
由于引力波天文学和黑洞成像的能力不断增长，我们很快就能着重确定潜伏在银河中心的天体暗物质是否是黑洞。SgrA*,我们银河系中最多产的天文无线电源之一，是广义相对论检验的重点。当前的质量和自旋限制预测，银河系的中心物体是超大质量且缓慢旋转的，因此可以保守地建模为史瓦西黑洞。然而，在超大体积的紧凑物体周围建立的吸积盘和天体物理环境的存在会使其几何形状显着变形，并使其观测科学成果复杂化。这里,我们研究了极端质量比二进制文件，该二进制文件由一个微小的次级物体吸入到超大质量的Zipoy-Voorhees紧凑物体上组成；广义相对论的最简单精确解，描述了静态，Schwarzschild时空的球形变形。我们检查了通用轨道的扁长和扁圆变形的大地测量，并通过轨道相空间中共振岛的存在重新评估了Zipoy-Voorhees时空的不可积性。通过将辐射损失与后牛顿技术相结合，我们在超大质量的Zipoy-Voorhees初级周围进化出恒星质量的次级物体，并在这些系统中找到清晰的不可积性印记。小学的独特结构，允许，不仅是典型的瞬态共振岛的单交叉，众所周知的非Kerr对象，但也有穿过几个岛屿的吸气，在短暂的时间内，这导致二进制引力波频率演化的多个故障。未来星载探测器的故障检测能力可以，因此,缩小奇异解的参数空间，否则,可以投射与黑洞相同的阴影。
