view Abstract Citations (1) References Co-Reads Similar Papers Volume Content Graphics Metrics Export Citation NASA/ADS Massive Stars in Quasi-Static Equilibrium. Iben, Icko, Jr. Abstract Starlike condensations of 106~10s solar masses have been suggested recently (Hoyle, F., and Fowler, W. A., Nature 1~7, 533) as the origin of the large energies 10~~ to 1061 erg required to account for strong radio sources. For masses of this size the equations of general relativity must be employed and, at the central temperatures to be expected (Tc~3 X 10~-3 X 1090K) the presence of electron-positron pairs must be included in the equation of state. In a preliminary survey, models in quasi-static equilibrium have been constructed for masses in the range 102 Mo to 10~ Mo and central temperatures in the range 1060K to 3X1090K. It is found that, with increasing central temperature and decreasing radius, the binding energy of a quasi-static configuration of fixed nucleon rest mass first increases through positive values, passes through a maximum, and then decreases rapidly to large negative values (-70 MeV per nucleon at Tc~3X1090K and M~106 Mo-tO9 Mo). The central temperature at which the binding energy first attains negative values follows the rough law Tc~7X10~ (Mo/M)0K. It is concluded that, after reaching the maximum in the binding energy curve, massive stars do not pass through quasi-static equilibrium stages. If, on reaching this maximum, matter in the massive star is stable against dynamic motions, then the star must break up into smaller components with an increase in the net binding energy of the system. If the matter is unstable dynamic motions, then central regions will implode and realistic models require a solution of the full dynamical equations of general relativity. A criterion is established for distinguishing between these two possibilities. This work was supported in part by the Office of Naval Research and in part by the National Aeronautics and Space Administration. Publication: The Astronomical Journal Pub Date: June 1963 DOI: 10.1086/108964 Bibcode: 1963AJ.....68..281I full text sources ADS |