S stars and s-process in the Gaia era

@article{Shetye2018SSA,
  title={S stars and s-process in the Gaia era},
  author={S. Shetye and Sophie Van Eck and Alain Jorissen and Hans Van Winckel and Lionel Siess and Stephane Goriely and Ana Escorza and Drisya Karinkuzhi and Bertrand Plez},
  journal={Astronomy \& Astrophysics},
  year={2018}
}
Context. S stars are late-type giants that are transition objects between M-type stars and carbon stars on the asymptotic giant branch (AGB). They are classified into two types: intrinsic or extrinsic, based on the presence or absence of technetium (Tc). The Tc-rich or intrinsic S stars are thermally pulsing (TP-)AGB stars internally producing s-process elements (including Tc) that are brought to their surface via the third dredge-up (TDU). The Tc-poor or extrinsic S stars gained their s… 

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