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arXiv · 1505.03756

Nucleosynthesis in a Primordial Supernova: Carbon and Oxygen Abundances in SMSS J031300.36-670839.31

Michael Bessell·Remo Collett·Stefan Keller·Anna Frebel·Alexander Heger·Andrew Casey·Thomas Masseron·Martin Asplund·Heather Jacobson·Karin Lind·Anna Marino·John Norris·David Yong·Gary Da Costa·Conrad Chan·Zazralt Magic·Brian Schmidt·Patrick Tisserand
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Abstract

SMSS J031300.36-670839.3 (hereafter SM0313-6708) is a sub-giant halo star, with no detectable Fe lines and large overabundances of C and Mg relative to Ca. We obtained VLT-UVES spectra extending to 3060 Angstroms showing strong OH A-X band lines enabling an oxygen abundance to be derived. The OH A-X band lines in SM0313-6708 are much stronger than the CH C-X band lines. Spectrum synthesis fits indicate an [O/C] ratio of 0.02 +- 0.175. Our high S/N UVES data also enabled us to lower the Fe abundance limit to [Fe/H]{3D},NLTE < -7.52 (3 sigma). These data support our previous suggestion that the star formed from the iron-poor ejecta of a single massive star Population III supernova.

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Michael Bessell, Remo Collett, Stefan Keller, Anna Frebel, Alexander Heger, Andrew Casey, Thomas Masseron, Martin Asplund, Heather Jacobson, Karin Lind, Anna Marino, John Norris, David Yong, Gary Da Costa, Conrad Chan, Zazralt Magic, Brian Schmidt, Patrick Tisserand. 2015-05-14. Nucleosynthesis in a Primordial Supernova: Carbon and Oxygen Abundances in SMSS J031300.36-670839.31. https://doi.org/10.1088/2041-8205%2F806%2F1%2Fl16

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