【作者】 康缈；

【导师】 郑小平；

【作者基本信息】 华中师范大学 ， 粒子物理与原子核物理， 2007， 博士

【摘要】 致密星是由于恒星塌缩而形成的一类致密天体，在它致密的核心中还可能发生强子物质到夸克物质的退禁闭相变。对致密星热演化的研究是了解它内部性质的一个重要途径。致密星的物态方程和旋转结构是研究中子星热演化的基础。文中分别介绍了包含强子相，混合相与夸克相的的中子星状态方程和它的旋转结构。研究了不同强子相参数和不同的s夸克质量对星体物态和结构的影响。结果显示，强子相状态方程变软以及s夸克质量增大都会使混合区域的密度范围变宽。s夸克质量的增大会抑制中子星内部纯夸克核的出现。中子星内部的退禁闭相变可能是一阶相变，相变过程中会有潜热释放，从而影响星体的热演化。退禁闭相变加热是由于星体的旋转而导致的一种加热机制，所以将混合相的状态方程作为输入，并结合旋转结构自洽地给出中子星退禁闭相变的加热率。对一系列恒星模型的估计发现单位核子退禁闭潜热释放平均约为0.1MeV。中子星退禁闭加热会显著的延缓星体的冷却，影响星体的热演化图象。对于内部有快中微子辐射过程的星体，强磁场时有加热效应的热演化曲线与观测数据(中等年龄脉冲星)是不矛盾的。而在弱磁场情况下，到10~9yrs之后星体表面温度依然高达10~5K，这可以较好地解释部分毫秒脉冲星的高温行为。综合分析、对比不同成份星体模型对于高温毫秒脉冲星的高温和快速旋转这两种观测特征的解释，我们发现高温毫秒脉冲星更有可能是混杂星。更多还原

【Abstract】 Compact stars are born in stellar gravitational collapse. The deconfinement phase transition is expected to occur at large densities in the cores of compact stars. The research of the thermal evolution of compact stars is of significant importance for understanding the properties of this mysterious object.The equation of state (EOS) and rotational structure are the base for investigating the thermal evolution of neutron stars. We introduce the EOS and internal structure of rotating neutron stars which include hadron phase, mixed phase and quark phase. The effect of different model bringing to EOS and configuration of star has been investigated. The results show that the soft EOS of hadron phase extends the width of mixed phase and so does the large mass of s quark. The mass of s quark is a prominent factor which influences deformation properties of rotating neutron stars. The large s quark mass can restrain the appearance of a pure quark matter core in neutron stars.Deconfinement phase transition in neutron stars are supposed to be of first order. The release of latent heat in the process of the deconfinement phase transition can affect thermal evolution of stars. Deconfinement phase transition coming from the stellar rotating is an important heating mechanism for compact stars’ cooling. By imputing the EOS of mixed phase, and then solving the equation of rotation structure, we self-consistently get the heating rate of deconfinement phase transition.Based on these models of stellar evolution, we get the average energy release of deconfinement phase transition of per nucleon being about 0.1 MeV.The deconfinement heating increase the surface temperature dramatically and influence the thermal evolution of neutron stars. We find the thermal evolution curves are consistent with the observational data (middle age pulsar) despite direct Urca process dominates neutrino emission. In the cases of weak field, stars could maintain high temperatures 10~5K even at older ages 10~9yrs. This feature could be suggested as a preferable explanation for high temperature of low-filed millisecond pulsars at late stage.Comparing the explanation of star models with different constitutions for high temperature mill-second pulsars, we suggest that the high temperature millsecond pulsars expect to be hybrid stars.更多还原