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Ezer, D., 1972: Theoretical evolution of a hydrogen-helium star of 3M☉ from the pre-main sequence to the core helium-exhaustion phase. Astrophys. Space Sci., 18, 226-245, doi:10.1007/BF00645294.
The evolution of a first-generation 3 M☉ star from the threshold of stability through the stage of helium exhaustion in the core has been studied. The total time elapsed is 4.174×108 yr and most of this time is spent in the blue-giant region of the H-R diagram. Hydrogen-burning near the Main Sequence occurs at a high central temperature via the proton-proton chain until the triple-alpha reactions generate a small amount of C12 toward the end of the hydrogen-burning phase. The corresponding evolution time is longer than that of a normal population I star with the same mass. The ignition of the triple-alpha processes begins in a mildly degenerate, small convective core while the star still has a high surface temperature. Helium-burning in the core, coupled with hydrogen- burning in the shell, occupies a period of about 1.8×107 yr, which is only one-third that of a normal star. The mass of the star interior to the hydrogen shell source has increased to a value of 0.50 M☉ near the end of core helium exhaustion. This region maintains an inhomogeneous composition composed of helium, carbon and oxygen
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