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Ezer, D.

Publications and source records attributed to Ezer, D..

16 records
All sourcesNASA NTRSDOE OSTI
NASA NTRS1972

Effects of sudden mixing in the solar core on solar neutrinos and ice ages.

Some numerical experiments with a solar model have been conducted in connection with the hypothesis regarding the effects of mixing in the solar core. Questions concerning a plausible mechanism by which such a mixing could be produced are explored. The variation of solar luminosity throughout the numerical experiments is shown. In connection with a great change in luminosity after a second mixing, it is suggested that the earth is presently undergoing an ice age.

Ezer, D.↗
NASA NTRS1971

The evolution of hydrogen-helium stars.

Investigation of the premain sequence evolution and the main sequence evolution of stars of 5, 10, 20, 30, 100, and 200 solar masses. Normal stars in this entire mass range normally convert hydrogen into helium by the CN-cycle on the main sequence. The present hydrogen-helium stars of 5 and 10 solar masses must reach higher central temperatures in order to convert hydrogen to helium by the proton-proton chains. Consequently, the mean densities in the stars are greater, and the surface temperatures are higher than in normal stars. In the stars of 20 solar masses and larger, the proton-proton chains do not succeed in supplying the necessary luminosity of the stars by the time the contraction has produced a central temperature near 10 to the 8th K. At that point triple-alpha reactions generate small amounts of C12, which then acts as a catalyst in the CN-cycle, the rate of which is then limited by the beta-decays occurring within the cycle. During the evolution of these more massive stars, the central temperature remains in the vicinity of 10 to the 8th K, and the surface temperature on the main sequence approaches 100,000.

Ezer, D.↗
NASA NTRS1968

Solar spin-down and neutrino fluxes.

Solar spin down and neutrino fluxes, explaining inability to detect neutrinos from sun by central hydrogen abundance assumption

Cameron, A. G. W.↗
NASA NTRS1967

Evolution of Stars of Low Mass

Evolutionary models in early and main sequence stages for low mass stars, using Hertzsprung- Russell diagram

Cameron, A. G. W.↗
NASA NTRS1963

THE EARLY EVOLUTION OF THE SUN

Sequence of models which confirms nayashis prediction that the early contracting sun should be highly luminous and fully convective

SOLAR PHYSICS↗