The evolution of supermassive Population III stars
| Autor: | L. Haemmerlé, Ralf S. Klessen, Alexander Heger, Tyrone E. Woods, Daniel J. Whalen |
|---|---|
| Rok vydání: | 2017 |
| Předmět: |
astro-ph.SR
Astrophysics::High Energy Astrophysical Phenomena Metallicity Population FOS: Physical sciences Astrophysics::Cosmology and Extragalactic Astrophysics Astrophysics 01 natural sciences massive [stars] Population III [stars] 0103 physical sciences Astrophysics::Solar and Stellar Astrophysics Protostar dark ages reionization first stars 010306 general physics education 010303 astronomy & astrophysics Stellar evolution Solar and Stellar Astrophysics (astro-ph.SR) STFC Astrophysics::Galaxy Astrophysics Physics education.field_of_study supermassive black holes [quasars] RCUK Astronomy Astronomy and Astrophysics Quasar early universe Accretion (astrophysics) Black hole Stars Astrophysics - Solar and Stellar Astrophysics Space and Planetary Science ST/P000509/1 Astrophysics::Earth and Planetary Astrophysics high-redshift [galaxies] |
| Zdroj: | Haemmerlé, L, Woods, T E, Klessen, R S, Heger, A & Whalen, D J 2018, ' The evolution of supermassive population III stars ', Monthly Notices of the Royal Astronomical Society, vol. 474, no. 2, pp. 2757-2773 . https://doi.org/10.1093/mnras/stx2919 |
| ISSN: | 1365-2966 0035-8711 |
| Popis: | Supermassive primordial stars forming in atomically-cooled halos at z∼15−20 are currently thought to be the progenitors of the earliest quasars in the Universe. In this picture, the star evolves under accretion rates of 0.1−1 M⊙ yr−1 until the general relativistic instability triggers its collapse to a black hole at masses of ∼105 M⊙. However, the ability of the accretion flow to sustain such high rates depends crucially on the photospheric properties of the accreting star, because its ionising radiation could reduce or even halt accretion. Here we present new models of supermassive Population III protostars accreting at rates 0.001−10 M⊙ yr−1, computed with the GENEVA stellar evolution code including general relativistic corrections to the internal structure. We use the polytropic stability criterion to estimate the mass at which the collapse occurs, which has been shown to give a lower limit of the actual mass at collapse in recent hydrodynamic simulations. We find that at accretion rates higher than 0.001 M⊙ yr−1 the stars evolve as red, cool supergiants with surface temperatures below 104 K towards masses >105M⊙, and become blue and hot, with surface temperatures above 105 K,only for rates ≲0.001 M⊙ yr−1. Compared to previous studies, our results extend the range of masses and accretion rates at which the ionising feedback remains weak, reinforcing the case for direct collapse as the origin of the first quasars. |
| Databáze: | OpenAIRE |
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