Equation Of State And The Computations Of Solar-like Models

As one of the most important input physics in the study of astrophysics, especially that of stellar model construction theory, Equation of state, together with nuclear-energy generation rate and opacity, is in the three basic ingredients that are required in stellar models. With the help of a certain stellar structure and evolution code, one can construct his own desired stellar model. Equation of state of an ideal gas is more simple and, for many astrophysical applications, crude recipes for the equation of state are quite adequate (e.g. an equation of state of an ideal gas.). However, in certain circumstances, for example, in heliosiesmology researches, high-quality helioseismological data require more elaborated theories to interpret and so, as a basic physical theory, equation of state itself has to describe more detailed and complicated states. For this purpose, work in equation of state as well as such like basic theories, especially in its non-ideal effects, becomes more and more pressing and useful.From the above viewpoint, this thesis first takes good time in surveying the history of equation of state and describing its general profile, with individual discussions of some useful versions of equation of state in stellar model theory at present. Then from the so called chemical picture standpoint with the basic physical technique of free-energy minimization, a detailed treatment in non-ideal effects of equation of state, particularly in Coulomb interactions between charged particles, is presented. In the last part of this thesis, such corrections are taken into solar-like models to be tentatively evaluated and tested. In the results, by comparing and analyzing the following corrections from the non-ideal Coulomb interactions to thestructures of low-mass stars, the correctness of this improved equation of state has been theoretically and practically verified.