Core collapse supernovae in the QCD phase diagram
Core collapse supernovae in the QCD phase diagram
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QCD 相图中的核心塌缩超新星
DOI：
10.1134/s1063778812050067
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发表时间：
2011
影响因子：
0.4
通讯作者：
S. Typel
中科院分区：
文献类型：
--
作者：
T. Fischer;D. Blaschke;M. Hempel;T. Klähn;R. Łastowiecki;M. Liebendörfer;G. Martínez;G. Pagliara;I. Sagert;Fredrik Sandin;J. Schaffner;S. Typel
我们比较了两类具有强子到夸克物质相变的混合状态方程在核坍缩超新星模拟中的应用。第一种模型采用夸克袋模型，描述了在低临界密度下向三味夸克物质的跃迁。第二种模型采用Polyakov-loop扩展的Nambu-Jona-Lasinio(PNJL)模型，其参数描述了在较高临界密度下到双味夸克物质的相变。这些模型对其转变密度具有明显不同的温度依赖性，这对超新星核心中可能出现的夸克物质是至关重要的。在反弹后早期的吸积相期间，只有当相变发生在足够低的密度时，才能发现夸克物质，就像基于袋子模型的研究中那样。在我们的PNJL参数化中，随着温度的升高而增加的临界密度阻止了夸克物质的形成。应用夸克袋模型得到的核心塌缩超新星的进一步演化导致了中心质子中子星的结构重新配置，在那里，除了一个质量很大的纯夸克物质核之外，还形成了一个强大的流体动力学激波，并在冲击波传播过程中释放了第二个中微子爆发。我们讨论了最近观测到的2M⊙脉冲星对夸克物质模型及其参数的自由选择的严重限制，以及它们对进一步研究QCD相图中的核心塌缩超新星的意义。
We compare two classes of hybrid equations of state with a hadron-to-quark matter phase transition in their application to core collapse supernova simulations. The first one uses the quark bag model and describes the transition to three-flavor quark matter at low critical densities. The second one employs a Polyakov-loop extended Nambu-Jona-Lasinio (PNJL) model with parameters describing a phase transition to two-flavor quark matter at higher critical densities. These models possess a distinctly different temperature dependence of their transition densities which turns out to be crucial for the possible appearance of quark matter in supernova cores. During the early post-bounce accretion phase quark matter is found only if the phase transition takes place at sufficiently low densities as in the study based on the bag model. The increase critical density with increasing temperature, as obtained for our PNJL parametrization, prevents the formation of quark matter. The further evolution of the core collapse supernova as obtained applying the quark bag model leads to a structural reconfiguration of the central protoneutron star where, in addition to a massive pure quark matter core, a strong hydrodynamic shock wave forms and a second neutrino burst is released during the shock propagation across the neutrinospheres. We discuss the severe constraints in the freedom of choice of quark matter models and their parametrization due to the recently observed 2M⊙ pulsar and their implications for further studies of core collapse supernovae in the QCD phase diagram.
DOI：
10.1088/0004-637x/694/1/664
发表时间：
2007-08
期刊：
The Astrophysical Journal
影响因子：
--
作者：
A. Marek;H. Janka
通讯作者：
A. Marek;H. Janka