Hydrogen Content and Energy-Productive Mechanism of White Dwarfs.

The equilibrium states of white dwarf stars of arbitrary mass and chemical composition are discussed. An improved expression for electronic conductivity and free electron density in the intermediate degenerate state is derived. It is found that no appreciable amount of hydrogen can exist in any white dwarf tar. The upper limit of hydrogen concentration (by weight) in the interior of a star having the mass of the sun is found to be 4 X 10-2 even in the absence of the carbon cycle. The corresponding value for stars of half the mass of the sun is 4.6 X 10-i. Investigations on stability show that a white dwarf star cannot live on the produced in its interior. The alternate mechanism of energy produced in the envelope is discussed. The equilibrium distribution of hydrogen in the envelope is also calculated. From this the observed fact of strong hydrogen lines in the spectrum of white dwarfs is explained.