发表机构
Amrita Vishwa Vidyapeetham（阿迈塔维迪亚佩塔姆大学）
机构由 AI 辅助整理，请以论文原文为准。AI 中文总结
本研究首次在完全广义相对论框架下，研究含暗能量核心的中子星的非径向f模振荡，发现暗能量软化状态方程并降低最大质量，且预测的引力波信号位于未来第三代探测器灵敏度范围内。
AI 中文摘要
我们首次利用完全广义相对论处理方法，研究了具有暗能量核心的中子星的非径向f模振荡。我们通过考虑核物质的相对论平均场模型和类似修正Chaplygin流体的暗能量描述来构建恒星轮廓。通过改变暗能量状态方程参数，我们计算了具有暗能量核心的中子星的恒星结构、f模振荡、潮汐形变率以及引力波能量和应变。我们的研究表明，暗能量的加入软化了状态方程，并降低了最大质量，与纯中子星相比。所获得的质量-半径值与来自大质量脉冲星（如PSR J0030+0451和PSR J0740+6620）的观测约束一致。我们发现，由跃迁密度决定的暗能量核心的范围在改变恒星结构和振荡特性方面起着关键作用，较低的跃迁密度在更宽的质量范围内产生显著变化。对于较高质量构型，f模频率和阻尼时间表现出系统性的修改，而f模频率与潮汐形变率之间的相关性仍与GW170817和GW190814的观测约束一致。此外，归一化振荡能量分布几乎保持普适性，仅对较高质量构型有最小偏差。最后，我们估算了与f模振荡相关的特征引力波应变，发现预测的信号位于未来第三代引力波探测器的灵敏度带内。
英文摘要
We investigate, for the first time, the non-radial $f$-mode oscillations of neutron stars (NSs) with a dark energy (DE) core utilising a fully general relativistic treatment. We construct the stellar profile by considering a relativistic mean field model for nuclear matter and a modified Chaplygin fluid like prescription for DE. We compute the stellar structure, $f$-mode oscillations, tidal deformability, and gravitational wave (GW) energy and strain of the NS with DE core by varying the DE equation of state (EoS) parameters. Our study reveals that the inclusion of DE softens EoS and reduces the maximum mass compared to the pure neutron star. The obtained mass-radius values are consistent with observational constraints from massive pulsars such as PSR J0030+0451 and PSR J0740+6620. We find that the extent of the DE core, determined by the transition density, plays a crucial role in modifying the stellar structure and oscillation properties, with lower transition densities producing appreciable changes over a wider mass range. The $f$-mode frequencies and damping times exhibit systematic modifications, for higher mass configurations, while the correlation between the $f$-mode frequency and tidal deformability remains consistent with observational constraints from GW170817 and GW190814. Further, the normalised oscillation energy distribution remains nearly universal, with only minimal deviations for the higher mass configurations. Finally, we estimate the characteristic GW strain associated with the $f$-mode oscillations and find that the predicted signals lie within the sensitivity band of future third generation GW detectors.
Comments13 pages, 11 figures
