Cooling of hypernuclear compact stars
Cooling of hypernuclear compact stars
复制标题
超核致密星的冷却
DOI：
10.1093/mnras/stx3318
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发表时间：
2017
影响因子：
4.8
通讯作者：
Weber, Fridolin
中科院分区：
文献类型：
--
作者：
Raduta, Adriana R;Sedrakian, Armen;Weber, Fridolin
我们研究了超核致密星的热演化构造超核物质的协变密度泛函理论和参数化产生的恒星序列包含两个太阳质量的对象。对于模拟中的输入，我们求解了超子扇区中的Bardeen-Cooper-Schrieffer能隙方程，并获得了Λ，Λ 0和Λ −超子谱中的能隙。对于质量M/M_∞ ≥ 1.5的模型，中微子冷却一般以超音直接Urca过程为主。在低质量恒星中，（Λp）+轻子通道是主要的直接Urca过程，而对于质量更大的恒星，纯超子通道（Λ-Λ）和（Λ-Λ）是主要的。超子配对强烈地抑制了Λ −s上的过程，在较小程度上也抑制了Λs上的过程。我们发现，如果考虑到超子对，中等质量1.5 ≤M/M ≤ 1.8模型的表面温度位于从热发射中子星推断的范围内。大多数M/M ≥ 2的大质量模型可能会通过（Λp）通道的直接Urca过程非常快地冷却，因为它们会在没有Λs和质子的S波配对的地方形成内核。
We study the thermal evolution of hypernuclear compact stars constructed from covariant density functional theory of hypernuclear matter and parametrizations which produce sequences of stars containing two-solar-mass objects. For the input in the simulations, we solve the Bardeen–Cooper–Schrieffer gap equations in the hyperonic sector and obtain the gaps in the spectra of Λ, Ξ0, and Ξ−hyperons. For the models with massesM/M⊙≥ 1.5 the neutrino cooling is dominated by hyperonic direct Urca processes in general. In the low-mass stars the (Λp) plus leptons channel is the dominant direct Urca process, whereas for more massive stars the purely hyperonic channels (Σ−Λ) and (Ξ−Λ) are dominant. Hyperonic pairing strongly suppresses the processes on Ξ−s and to a lesser degree on Λs. We find that intermediate-mass 1.5 ≤M/M⊙≤ 1.8 models have surface temperatures which lie within the range inferred from thermally emitting neutron stars, if the hyperonic pairing is taken into account. Most massive models withM/M⊙≃ 2 may cool very fast via the direct Urca process through the (Λp) channel because they develop inner cores where theS-wave pairing of Λs and proton is absent.