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arXiv · 2102.01076

Metal-poor Stars Observed with the Automated Planet Finder Telescope. III. CEMP-no Stars are the Descendant of Population III Stars

Nour Aldein Almusleh·Ali Taani·Sergen Özdemir·Maria Rah·Mashhoor A. Al-Wardat·Gang Zhao·Mohammad K. Mardini
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Abstract

In this study, we report a probabilistic insight into the stellar mass and supernovae (SNe) explosion energy of the possible progenitors of five CEMP-no stars. This was done by a direct comparison between the abundance ratios [X/Fe] of the light-elements and the predicted nucleosynthetic yields of SN of high-mass metal-free stars. This comparison suggests possible progenitors with stellar mass range of 11 - 22\,M$_{\odot}$ and explosion energies of $0.3 - 1.8 \times 10^{51}$\,erg. The coupling of the chemical abundances with kinematics derived from $Gaia$ DR2 suggests that our sample do not enter the outer-halo region. In addition, we suggest that these CEMP-no stars are not $Gaia$-Sausage nor $Gaia$-Sequoia remnant stars, but another accretion event might be responsible for the contribution of these stars to the Galactic Halo of the Milky-Way.

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Nour Aldein Almusleh, Ali Taani, Sergen Özdemir, Maria Rah, Mashhoor A. Al-Wardat, Gang Zhao, Mohammad K. Mardini. 2021-02-01. Metal-poor Stars Observed with the Automated Planet Finder Telescope. III. CEMP-no Stars are the Descendant of Population III Stars. https://doi.org/10.1002/asna.202113867

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