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arXiv · 1908.02500

EC 22536-5304: SALT identifies a new lead-rich intermediate helium subdwarf

C. Simon Jeffery·Brent Miszalski
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Abstract

SALT spectra of the helium-rich hot subdwarf EC22536-5304 show strong absorption lines of triply-ionized lead. Analysis of the HRS spectrum and a follow-up SALT/RSS spectrum show EC22536-5304 to have surface properties (temperature, gravity, helium/hydrogen ratio) similar to other heavy-metal subdwarfs. With a lead overabundance of 4.8 dex relative to solar, EC22536-5304 is the most lead-rich intermediate helium subdwarf discovered so far.

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C. Simon Jeffery, Brent Miszalski. 2019-08-07. EC 22536-5304: SALT identifies a new lead-rich intermediate helium subdwarf. https://doi.org/10.1093/mnras%2Fstz2231

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