The effects of diffusion in hot subdwarf progenitors from the common envelope channel

  title={The effects of diffusion in hot subdwarf progenitors from the common envelope channel},
  author={Conor M Byrne and C. Simon Jeffery and Christopher A. Tout and Haili Hu},
  journal={Monthly Notices of the Royal Astronomical Society},
  • C. ByrneC. Jeffery Haili Hu
  • Published 1 February 2018
  • Physics, Geology
  • Monthly Notices of the Royal Astronomical Society
Diffusion of elements in the atmosphere and envelope of a star can drastically alter its surface composition, leading to extreme chemical peculiarities. We consider the case of hot subdwarfs, where surface helium abundances range from practically zero to almost 100 percent. Since hot subdwarfs can form via a number of different evolution channels, a key question concerns how the formation mechanism is connected to the present surface chemistry. A sequence of extreme horizontal branch star… 

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