Open AccessThe effect of electron screening on the structure of crystals in degenerate stars
Author(s) -
A. A. Kozhberov
Publication year - 2020
Publication title -
journal of physics. conference series
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 0.21
H-Index - 85
eISSN - 1742-6596
pISSN - 1742-6588
DOI - 10.1088/1742-6596/1697/1/012017
Subject(s) - physics , electron , degenerate energy levels , lattice (music) , ion , fermi gas , condensed matter physics , atomic physics , fermi energy , stars , neutron star , quantum mechanics , astrophysics , acoustics
The neutron stars crust and white dwarfs consist of a degenerate relativistic electron gas and atomic nuclei arranged into a crystal lattice. The type of lattice that ions form may depend on many parameters, for example, on the external magnetic field, temperature ( T ), and ion number density ( n ). In this paper, we consider the effect of electron background polarization on the type of lattice at T = 0. Two approximations are used to describe this background. If it is described by the Thomas-Fermi model, the influence of polarization is determined only by the parameter κ TF a , where κ TF is the Thomas-Fermi wave number, a = (4π n /3) −1/3 is the radius of the ion sphere and at κ TF a ⋦ 1 the bcc lattice has the lowest energy. On the other hand, if we use the random-phase approximation for the electron dielectric function, the energy of the static lattice will be a function of κ TF and the relativistic electron parameter x r . In this case, the bcc lattice possesses the lowest energy at κ TF a < 0.28 and any x r , while at higher κ TF a the formation of other lattice in consideration (fcc and hcp) is possible.