Abstract
The characteristics of degenerate dwarfs-core radius, mass, and energy, thickness of their outer layers-are calculated based on a mechanical-equilibrium equation in a five-parameter, two-phase compositemodel with an isothermal core and a non-degenerate outer region. An accurate equation of state for the partially degenerate, ideal, relativistic electron gas of the core is used together with a polytropic approximation for the outer layers. The model parameters are determined using the known masses, radii, and luminosities of observed DA white dwarfs. A region where dwarfs can exist is identified in a plot of core temperature vs. the relativity parameter at the center of the star, and the dependence of the core temperature on the effective temperature of the photosphere is constructed.
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Original Russian Text © M.V. Vavrukh, S.V. Smerechinskii, 2013, published in Astronomicheskii Zhurnal, 2013, Vol. 90, No. 12, pp. 993-1065.
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Vavrukh, M.V., Smerechinskii, S.V. Hot degenerate dwarfs in a two-phase model. Astron. Rep. 57, 913–983 (2013). https://doi.org/10.1134/S1063772913100065
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DOI: https://doi.org/10.1134/S1063772913100065