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arXiv · 1202.2378

Detection of the Second r-process Peak Element Tellurium in Metal-Poor Stars

Ian U. Roederer·James E. Lawler·John J. Cowan·Timothy C. Beers·Anna Frebel·Inese I. Ivans·Hendrik Schatz·Jennifer S. Sobeck·Christopher Sneden
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Abstract

Using near-ultraviolet spectra obtained with the Space Telescope Imaging Spectrograph onboard the Hubble Space Telescope, we detect neutral tellurium in three metal-poor stars enriched by products of r-process nucleosynthesis, BD+17 3248, HD 108317, and HD 128279. Tellurium (Te, Z=52) is found at the second r-process peak (A=130) associated with the N=82 neutron shell closure, and it has not been detected previously in Galactic halo stars. The derived tellurium abundances match the scaled solar system r-process distribution within the uncertainties, confirming the predicted second peak r-process residuals. These results suggest that tellurium is predominantly produced in the main component of the r-process, along with the rare earth elements.

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Ian U. Roederer, James E. Lawler, John J. Cowan, Timothy C. Beers, Anna Frebel, Inese I. Ivans, Hendrik Schatz, Jennifer S. Sobeck, Christopher Sneden. 2012-02-10. Detection of the Second r-process Peak Element Tellurium in Metal-Poor Stars. https://doi.org/10.1088/2041-8205%2F747%2F1%2Fl8

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