On the Stability of Stellar Models, with Remarks on the Origin of Novae.

Abstract

view Abstract Citations (3) References Co-Reads Similar Papers Volume Content Graphics Metrics Export Citation NASA/ADS On the Stability of Stellar Models, with Remarks on the Origin of Novae. Tolman, Richard C. Abstract A brief review is first given of the results previously obtained by various investiga- tors concerning the secular stability of stars, the stability of pulsating stars, and the rela- tive stabifity of the processes of radiative and of convective thermal transfer in the in- terior of stars. The present article then considers, as a further aspect of the general problem, the stability of stars toward inl5nitesimal, instantaneous fluctuations in the distribution of stellar fluid. The necessary and sufficient criterion for such stability is that the available potential energy of the stellar model shall be a minimum toward reversible, adiabatic variations in the distribution of fluid. Setting up the integral which expresses the available potential energy, and applying the calculus of variations, it is found that this integral in general automatically satisfies all tests for a mini- mum, except that of Jacobi as to the location of conjugate points, where special in- vestigation must be made in each separate case. Carrying out such investigations of the Jacobi test as are readily feasible, it is found that there is no reason to expect instability of the kind under consideration in the case of simple stellar models having radiative (or convective) thermal transfer throughout. It is also found, however, that the presence of a central convective zone or of a convective zone just under the surface of a star, other- wise having radiative thermal transfer, can introduce factors tending toward failure of the Jacobi test. Further investigation would be necessary to determine whether in- stability arising in such a manner could actually play an important role in stellar be- havior. The article closes with remarks as to various explanations for stellar novae which have been proposed, including the tentative new suggestion that their origin might be due to instability arising from failure of the integral of available potential energy to satisfy the Jacobi test for a minimum Publication: The Astrophysical Journal Pub Date: November 1939 DOI: 10.1086/144123 Bibcode: 1939ApJ....90..568T full text sources ADS |