Lifting the Veil on Quark Matter in Compact Stars with Core g-mode Oscillations

Compact stars containing quark matter may masquerade as neutron stars in the range of measured mass and radius, making it difficult to draw firm conclusions on the phase of matter inside the star. The sensitivity of core g-mode oscillations to the presence of a mixed phase may alleviate this difficulty. In hybrid stars that admit quark matter in a mixed phase, the g-mode frequency rises sharply due to a marked decrease in the equilibrium sound speed. Resonant excitation of g-modes can leave an imprint in the waveform of coalescing binary compact stars. We present analytic and numeric results to assess the sensitivity displayed by g-mode oscillations to quark matter in a homogeneous or mixed phase and also compute relevant damping times in quark matter due to viscosity.

包含夸克物质的致密星在测量到的质量和半径范围内可能伪装成中子星，这使得很难对星内物质的相态得出确定的结论。核心重力模式振荡对混合相存在的敏感性可能缓解这一困难。在允许夸克物质处于混合相的混合星中，由于平衡声速显著下降，重力模式频率急剧上升。重力模式的共振激发会在并合的双致密星的波形中留下印记。我们给出解析和数值结果，以评估重力模式振荡对均匀相或混合相中的夸克物质所表现出的敏感性，并且还计算了由于粘性在夸克物质中的相关阻尼时间。