Numerical simulations of black hole-neutron star mergers in scalar-tensor gravity
Numerical simulations of black hole-neutron star mergers in scalar-tensor gravity
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DOI：
10.1103/physrevd.107.124051
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发表时间：
2023-04
影响因子：
5
通讯作者：
Sizheng Ma;V. Varma;L. Stein;F. Foucart;Matthew D. Duez;Lawrence E. Kidder;H. Pfeiffer;M. Scheel
中科院分区：
文献类型：
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作者：
Sizheng Ma;V. Varma;L. Stein;F. Foucart;Matthew D. Duez;Lawrence E. Kidder;H. Pfeiffer;M. Scheel
我们提出了标量调整器（ST）重力中的黑洞 - 中子星的合并的数值余量模拟，其二进制参数与重力波事件GW200115一致。在此探索性模拟中，我们考虑了Brans-Dicke理论的Damour-eSposito-Farese扩展，并通过选择已知约束的边缘的状态和ST理论参数的软方程来最大程度地提高自发标量的影响。我们将重力波（包括张量和标量（呼吸）模式）推断为未来的无效。合并之前的数值波形经历了〜22波周期，并且与灵感后的牛顿后理论的预测非常吻合。我们发现，由于偶极辐射引起的ST系统的发展速度快于其一般性（GR）对应物，并在GR对应物之前合并了全重力波周期。在参数估计的背景下，这可以轻松区分ST波形和GR。但是，我们发现偶极子辐射的效果可能会随着Inspiral阶段的NS潮汐变形性而部分退化，并且必须进行完整的贝叶斯分析以充分了解GR中的ST和二进制参数之间的脱位。
We present a numerical-relativity simulation of a black hole - neutron star merger in scalar-tensor (ST) gravity with binary parameters consistent with the gravitational wave event GW200115. In this exploratory simulation, we consider the Damour-Esposito-Farese extension to Brans-Dicke theory, and maximize the effect of spontaneous scalarization by choosing a soft equation of state and ST theory parameters at the edge of known constraints. We extrapolate the gravitational waves, including tensor and scalar (breathing) modes, to future null-infinity. The numerical waveforms undergo ~ 22 wave cycles before the merger, and are in good agreement with predictions from post-Newtonian theory during the inspiral. We find the ST system evolves faster than its general-relativity (GR) counterpart due to dipole radiation, merging a full gravitational-wave cycle before the GR counterpart. This enables easy differentiation between the ST waveforms and GR in the context of parameter estimation. However, we find that dipole radiation's effect may be partially degenerate with the NS tidal deformability during the late inspiral stage, and a full Bayesian analysis is necessary to fully understand the degeneracies between ST and binary parameters in GR.