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arXiv · 2203.15693

Simulated observations of heavy elements with CUBES

H. Ernandes·B. Barbuy·B. Castilho·C. J. Evans·G. Cescutti
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Abstract

We investigate the feasibility of robust abundances for selected neutron-capture elements (Ge, Bi, Hf, U) from near-UV spectroscopy with the CUBES instrument now in development for the Very Large Telescope. We use the CUBES end-to-end simulator to synthesise observations of the Ge I 3039 {\AA} and Hf II 3400 and 3719 {\AA} lines in a very metal-poor star, using the well-studied star CS 31082-001 as a template. From simulated 4 hr exposures, we recover estimated abundances to $\pm$0.1 dex for Ge for U $\sim$ 14.25 mag., and for Hf for U = 18 mag. These performances neatly highlight the powerful gain of CUBES for near-UV observations of targets that are two-to-three magnitudes fainter than the existing observations of CS 31082-001 (U = 12.5 mag.). We also investigate the weak Bi I 3025 {\AA} and U II 3860 {\AA} lines (for U $\sim$ 14.25 and 16mag., respectively), finding that simulated 4hr exposures should provide upper limits to these observationally challenging lines.

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H. Ernandes, B. Barbuy, B. Castilho, C. J. Evans, G. Cescutti. 2022-03-29. Simulated observations of heavy elements with CUBES. https://doi.org/10.1007/s10686-021-09829-2

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