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

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 نشر من قبل Simon Jeffery
 تاريخ النشر 2019
  مجال البحث فيزياء
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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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