Polytropes:Applications in Astrophysics and Related Fields

摘要

Polytrope comes from the Ancient Greek word polytropos or polutropos.The basic meaning is'of many turns'.Polytropes are equilibrium gas spheres.The polytropic equation of state,relating pressure(P)and density(rho)as a function of position r,is P(r)=K rho(r) (n + l) where K is a constant and n is polytropic index.This equation of state with the equation of hydrostatic equilibrium will provide a single relation for pressure or density as a function of position.In astrophysical systems this equation basically solves the problem of stellar structure.Solutions are called polytropes of a particular index n.