中子星短时标热演化研究

It is believed that the comparison of the observed surface temperature data and the thermal evolution simulation of neutron stars (NSs) will effectively constraint the equation of state of cold dense nuclear matter. Especially，in 2010, Heinke and Ho find that the temperature of the Cas A NS has decreased about 4% in the last ten years by anlysing the data of Chandra satelate. This is the first time that one ever get the precise temperature evloution of a NS, and its rapid cooling fling down a challenge to the NS cooling theory.So far there are three different models for the explaination of the short-term thermal evolution of Cas A NS,namely,"neurtron-superfluidity-triggering mechanism", "rotation-driven direct urca process model" and "r-mode heating switching-off mechanism" proposed by our team. This project will: (a) Modify "r-mode heating switching-off mechanism" by considering the previously ignored thermal relaxtion in the crust of NS. (b) Study the three different models comparatively so that one can exclude certain models by the observation data in the following decade. (c) Investigate the second order r-mode heating effect and the "r-mode heating switching-off mechanism" of hadron-quark hybrid stars,which will not only explain the rapid cooling of Cas A NS, but also improve the explaination of the two young and hot pulsar data (PSR B0531+21 and RX J0822-4300) .

中子星表面温度观测数据与热演化理论模拟的对比研究，将有力地限制冷密核物质性质。特别是2010年，Heinke和 Ho分析了Chandra卫星对Cas A中子星的观测数据，发现过去10年内急剧下降4%。这是第一颗精确给出温度演化的中子星，它的快速冷却对中子星理论提出了挑战。解释Cas A 短时标热演化行为的模型目前仅有三个："核子超流触发机制"、"转动驱动直接Urca过程"模型以及本项目负责人所在课题组提出的"r模加热关闭机制"。本项目将：1）引入先前研究中被忽略的中子星壳层热弛豫过程，完善"r模加热关闭机制"。2）对比研究Cas A中子星快速冷却的三种模型，可能通过未来十年左右的观测排除其中某些模型。3）研究强子-夸克混杂星的二阶r模加热效应和"r模加热关闭机制"，可能在解释Cas A中子星快速冷却的同时，更好地解释两颗最热的年轻脉冲星数据（PSR B0531+21和RX J0822-43

中子星表面温度观测数据与热演化理论模拟的对比研究，将有力地限制冷密核物质性质。本项目理论模拟了冷密核物质组成的致密星体的r模不稳定性和热演化，并与致密星相关天文观测, 特别是表面热辐射的观测数据进行了对比。具体进行了以下几个方面的研究：（1）研究了奇异夸克星r模不稳定性，发现只有对袋模型进行修正，考虑进口袋内夸克间相互作用时，才能较好地解释小质量X射线双星的热辐射和转动频率观测数据。（2）研究了小质量裸奇异星r模不稳定性，发现质量在约0.1 M⊙～0.2 M⊙以下的裸奇异星可以具有716Hz的极限旋转频率。（3）考虑进热弛豫过程，研究了带壳层正常及色超导奇异星的热演化，解释了观测到的中心致密天体（CCOs）的热数据。（4）研究局域电中性强子—夸克相变中的能量释放，该研究工作可应用于混合星的热演化研究中。