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arXiv 2007.08493astro-ph.HEastro-ph.SRnucl-th
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GW190814作为具有奇异自由度的大质量快速旋转中子星

GW190814 as a massive rapidly-rotating neutron star with exotic degrees of freedom

Kent State University(肯特州立大学);Frankfurt Institute for Advanced Studies(法兰克福高等研究所);California State University Long Beach(加州州立大学长滩分校);University of California, Berkeley(加州大学伯克利分校);Ohio University(俄亥俄大学)

V. Dexheimer, R. O. Gomes, T. Klähn, S. Han, M. Salinas

AI总结:

研究包含超子和夸克的物态方程模型能否产生大质量中子星,发现引入夸克矢量相互作用和非标准自矢量相互作用后,快速旋转模型可达2.5倍太阳质量,解释GW190814事件。

摘要:

在最近紧凑星并合事件GW190814中观测到的大质量次级天体的背景下,我们研究了从几种包含奇异自由度(如超子和夸克)的物态方程模型产生大质量中子星的可能性。我们的工作表明,当引入夸克矢量相互作用和非标准自矢量相互作用时,最先进的相对论平均场模型可以产生达到$\gtrsim 2.05\,\Msun$的大质量恒星,同时与引力波事件和X射线脉冲星观测结果高度一致。特别是,我们提出了手征平均场(CMF)模型的一个新版本,其中不同的夸克退禁闭势允许具有纯夸克核的稳定恒星。当考虑快速旋转时,我们的模型产生的恒星质量接近并在某些情况下超过$2.5\,\Msun$。我们发现,在这种情况下,由于恒星中心密度的变化,快速旋转并不一定会抑制奇异自由度,但需要比非旋转恒星允许的更多的重子数。对于纯夸克星则并非如此,它们可以轻松达到$2.5\,\Msun$,并且仍然拥有与稳定非旋转恒星大致相同的重子数。我们还简要讨论了具有大量重子数的快速旋转恒星的可能起源及其稳定性,展示了GW190814事件如何与包含夸克的恒星作为其前身之一相关联。

英文摘要:

In the context of the massive secondary object recently observed in the compact-star merger GW190814, we investigate the possibility of producing massive neutron stars from a few different equation of state models that contain exotic degrees of freedom, such as hyperons and quarks. Our work shows that state-of-the-art relativistic mean field models can generate massive stars reaching $\gtrsim 2.05\,\Msun$, while being in good agreement with gravitational-wave events and x-ray pulsar observations, when quark vector interactions and non-standard self-vector interactions are introduced. In particular, we present a new version of the Chiral Mean Field (CMF) model in which a different quark-deconfinement potential allows for stable stars with a pure quark core. When rapid rotation is considered, our models generate stellar masses that approach, and in some cases surpass $2.5\,\Msun$. We find that in such cases fast rotation does not necessarily suppress exotic degrees of freedom due to changes in stellar central density, but require a larger amount of baryons than what is allowed in the non-rotating stars. This is not the case for pure quark stars, which can easily reach $2.5\,\Msun$ and still possess approximately the same amount of baryons as stable non-rotating stars. We also briefly discuss possible origins for fast rotating stars with a large amount of baryons and their stability, showing how the event GW190814 can be associated with a star containing quarks as one of its progenitors.

机构、总结、中文摘要均由AI分析而来,可能存在错误,请以论文正文为准。

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