中子星的两个分支--2兆太阳脉冲星与SN1987A的调和
Two branches of neutron stars - reconciling a 2M_sun pulsar and SN1987A
摘要：
Brown和Bethe（1995）通过对SN 1987 A的分析得出结论，冷中子星的最大质量较低，M_max~1.5M_sun。如此低的M_（max）值是由于K介子在星核中的凝聚而引起的，这意味着质量过大的去质子化质子中子星坍缩成黑洞。这自然可以解释SN 1987 A残骸中为何没有中子星。另一方面，最近对PSR J0751 + 1807的质量评估给出了M_max> 2M_sun。这与最初的贝特-布朗模型相矛盾，但可以在本信中提出的情景中得到调和。我们考虑两种类型的高密度软化的致密物质模型，由于从一个非奇怪的N相的物质的奇异携带相S：K介子凝聚和夸克的解除禁闭的过渡。考虑了两种在恒星核坍缩中形成中子星的情形。在第一种情况下，在足够热和密度的超新星核心中，S相的成核足够快，从而形成S相核心，这意味着M_max = M ^S_max =~1.5M_sun。在第二种情况下，S相在中子星诞生时的成核速度太慢，无法实现，恒星变得很冷，但没有形成S相核心。然后，恒星质量可以通过吸积增加，直到达到中心密度ρ_crit，并形成S相。这N支中子星终止于M = M_crit，我们选择了几种满足M ^N_max> 2M_sun必要条件的N相模型，并将它们与K介子凝聚和夸克解除禁闭模型相结合。对于K介子凝聚，我们得到M_crit =~M ^S_max =~1.5M_sun，这被PSR J0751 + 1807排除了。相反，对于夸克解除禁闭的EOS，我们得到M_crit =~M ^N_max> 2M_sun，这使SN 1987 A和PSR J0751 + 1807协调一致。
英文摘要：
The analysis of SN1987A led Brown and Bethe (1995) to conclusion, that the maximum mass of cold neutron stars is low, M_max ~ 1.5M_sun. Such a low M_max, due to a kaon condensation in the stellar core, implies collapse of a too massive deleptonized protoneutron star into a black hole. This would naturally explain the lack of a neutron star in the SN1987A remnant. On the other hand, recent evaluation of mass of PSR J0751+1807 gives M_max > 2M_sun. This contradicts the original Bethe-Brown model, but can be reconciled within scenarios proposed in the present Letter. We consider two types of dense matter models with high-density softening, due to a transition from a non-strange N-phase of matter to a strangeness carrying phase S: kaon condensation and deconfinement of quarks. Two scenarios of neutron star formation in stellar core collapse are considered. In the first scenario, realized in sufficiently hot and dense supernova cores, nucleation of an S-phase is sufficiently rapid so as to form an S-phase core, and implying M_max = M^S_max =~ 1.5M_sun. In the second scenario, nucleation of the S-phase at neutron star birth is too slow to materialize, and the star becomes cold without forming an S-phase core. Then, stellar mass can increase via accretion, until central density ρ_crit is reached, and the S phase forms. This N branch of neutron stars ends at M=M_crit. We select several models of N-phase satifying the necessary condition M^N_max > 2M_sun and combine them with models of kaon condensation and quark deconfinement. For kaon condensation, we get M_crit =~ M^S_max =~ 1.5M_sun, which is ruled out by PSR J0751+1807. On the contrary, for the EOSs with quark deconfinement we get M_crit =~ M^N_max > 2M_sun, which reconciles SN1987A and PSR J0751+1807.
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。
