论文标题
在强磁场下中子恒星中的面食相
Pasta phases in neutron stars under strong magnetic fields
论文作者
论文摘要
在目前的工作中,我们在中子恒星的最内层地壳中考虑了在相对论平均场描述的框架内存在强磁场下的核物质。为了讨论状态方程在外壳结构上的密度依赖性,考虑了两个具有不同斜率的对称能量的模型。在共存的阶段方法中描述了$β$平衡中的非均匀物质,并讨论了包括异常磁矩的效果。考虑了面食结构的五种不同的几何形状。结果表明,强磁场会导致中子恒星的内壳的延伸,并出现一系列断开的非均匀质量区域,而无均匀的物质区域上方存在于无效磁场。此外,我们观察到,在这些断开的区域,对于磁场的某些值,所有五个不同的簇几何形状都会发生,并且气体密度接近簇密度。同样,中子星形核核过渡的压力远大于零磁场获得的压力。存在强磁场的另一个显着效果是质子部分的增加,有利于质子在气体背景中的出现。
In the present work, we consider nuclear matter in the innermost crust of neutron stars under the presence of a strong magnetic field within the framework of a relativistic mean-field description. Two models with a different slope of the symmetry energy are considered in order to discuss the density-dependence of the equation of state on the crust structure. The non-homogeneous matter in $β$-equilibrium is described within the coexisting phases method, and the effect of including the anomalous magnetic moment is discussed. Five different geometries for the pasta structures are considered. It is shown that strong magnetic fields cause an extension of the inner crust of the neutron stars, with the occurrence of a series of disconnected non-homogeneous matter regions above the one existing for a null magnetic field. Moreover, we observed that in these disconnected regions, for some values of the magnetic field, all five different cluster geometrical shapes occur, and the gas density is close to the cluster density. Also, the pressure at the neutron star crust-core transition much larger than the pressure obtained for a zero magnetic field. Another noticeable effect of the presence of strong magnetic fields is the increase of the proton fraction, favoring the appearance of protons in the gas background.