论文标题
具有重力辐射和粘度的高质量紧凑型恒星的振荡
Oscillations of hypermassive compact stars with gravitational radiation and viscosity
论文作者
论文摘要
二进制中子星星合并（例如多中音GW170817事件）可能会产生高质量紧凑的物体，这些物体受到恒星内流体的内部循环的支持。我们计算它们由重力波辐射和剪切粘度驱动的不稳定振荡模式，将它们建模为三轴riemann椭圆形。我们在扰动状态下工作，其中重力辐射反作用力以2.5杆 - 纽顿秩序考虑在内，并找到具有耗散时间尺度$ \ gtrsim 1 $ ms的不稳定模式，这与合并过度零碎的过度磨损相关。我们表明，世俗的不稳定性由重力波辐射主导。如果包括剪切粘度，它可以增加生长时间甚至稳定不稳定的模式，但是它必须具有比冷中子恒星预测的几个数量级的值。
Binary neutron star mergers, such as the multimessenger GW170817 event, may produce hypermassive compact objects which are supported against collapse by the internal circulation of the fluid within the star. We compute their unstable modes of oscillations driven by gravitational wave radiation and shear viscosity, modeling them as triaxial Riemann ellipsoids. We work in a perturbative regime, where the gravitational radiation reaction force is taken into account at 2.5-post-Newtonian order and find unstable modes with dissipation timescales $\gtrsim 1$ ms which are relevant to the transient state of a hypermassive remnant of a merger. We show that the secular instabilities are dominated by gravitational wave radiation. If the shear viscosity is included, it can increase the growth times or even stabilize the unstable modes, but it must have values several orders of magnitude larger than predicted for cold neutron stars.
