Pregalactic-primordial low-mass stars

Date

1987-8

Author

Kızıloğlu, Nilgün Gülşan
Eryurt, Dilhan Ezer

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The Main-Sequence positions as well as the evolutionary behavior of Population III stars up to an evolution age of 2×1010 yr, taking this time as the age of the Universe, have been investigated in the mass range 0.2 and 0.8M ⊙. While Population III stars with masses greater than 0.3M ⊙ develop a radiative core during the approach to the Main Sequence, stars with masses smaller than 0.3M ⊙ reach the Main Sequence as a wholly convective stars. Population III stars with masses greater than 0.5M ⊙ show a brightening of at most 2.2 in bolometric magnitude when the evolution is terminated as compared to the value which corresponds to zero-age Main Sequence. The positions of stars with masses smaller than 0.5M ⊙ remain almost the same in the H-R diagram. If Population III stars have formed over a range of redshifts, 6<Z<1500, the original starlight of low-mass Population III stars could now be the part of infrared and/or microwave background spectrum between 7 and 1400 μm.

Subject Keywords

Space and Planetary Science, Astronomy and Astrophysics

URI

https://hdl.handle.net/11511/51986

Journal

Astrophysics and Space Science

DOI

https://doi.org/10.1007/bf00661255

Collections

Department of Physics, Article

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Citation Formats

N. G. Kızıloğlu and D. E. Eryurt, “Pregalactic-primordial low-mass stars,” Astrophysics and Space Science, pp. 83–90, 1987, Accessed: 00, 2020. [Online]. Available: https://hdl.handle.net/11511/51986.