论文标题
灵感中子恒星二进制的演变：潮汐相互作用和轨道偏心的影响
Evolution of inspiralling neutron star binaries: effects of tidal interactions and orbital eccentricities
论文作者
论文摘要
在Ligo/Pirgo带中排放引力波（GWS）时，动态形成的中子星（NS）二进制物可能具有明显的偏心率。我们使用一组混合方程研究了这种偏心的NS NS二进制文件中的潮汐效应。 NS被建模为可压缩的椭圆形，由于潮汐力可能会非线性变形，而轨道演化则以纽顿后（PN）理论处理高达2.5-pn的顺序。我们发现通常，潮汐相互作用可以加速灵感，并导致轨道频率和相移。对于圆形灵感，我们的计算在较大的二元间分离下再现了先前的线性结果，但在小分离下纳入了NS的动态响应。对于偏心的灵感，频率和相位偏移在折缘通道附近相当大，振动振幅随偏心率而增加。结果，GW阶段也受到潮汐效应的显着影响。在合并时，累积的GW相移可能可以达到10多个弧度（对于典型的NS质量$ 14M_ \ odot $和半径11.6公里），比圆形Inspiral Case大得多。尽管偏心合并的事件速率可能很低，但此类合并的检测可能会对状态的NS方程提供有用的约束。
Neutron star (NS) binaries formed dynamically may have significant eccentricities while emitting gravitational waves (GWs) in the LIGO/VIRGO band. We study tidal effects in such eccentric inspiralling NS binaries using a set of hybrid equations. The NS is modelled as a compressible ellipsoid, which can deform nonlinearly due to tidal forces, while the orbit evolution is treated with the post-Newtonian (PN) theory up to 2.5-PN order. We find that in general, the tidal interaction can accelerate the inspiral, and cause orbital frequency and phase shifts. For circular inspirals, our calculations reproduce previous linear result at large binary separations, but incorporate the dynamical response of the NS at small separations. For eccentric inspirals, the frequency and phase shifts oscillate considerably near pericenter passages, and the oscillating amplitudes increase with eccentricities. As a result, the GW phase is also significantly influenced by the tidal effect. At merger, the cumulative GW phase shift can reach more than 10 radians (for typical NS mass $1.4M_\odot$ and radius 11.6 km), much larger than the circular inspiral case. Although the event rate of eccentric NS mergers is likely low, the detection of such mergers could provide a useful constraint on the NS equation of state.
