English

Modeling the formation of the $^{13}$C neutron source in AGB stars

Solar and Stellar Astrophysics 2020-10-27 v2

Abstract

A major source of uncertainty in AGB models is the partial-mixing process of hydrogen, required for the formation of the so-called 13^{13}C pocket. Among the attempts to derive a self-consistent treatment of this physical process, there are 2D and 3D simulations of magnetic buoyancy. The 13^{13}C pocket resulting from mixing induced by magnetic buoyancy extends over a region larger than those so far assumed, showing an almost flat 13^{13}C distribution and a negligible amount of 14^{14}N. Recently, it has been proved to be a good candidate to match the records of isotopic abundance ratios of ss-elements in presolar SiC grains. However, up to date such a magnetic mixing has been applied in post-process calculations only, being never implemented in a stellar evolutionary code. Here we present new stellar models, performed with the 1-d hydrostatic FUNS evolutionary code, which include magnetic buoyancy. We comment the resulting ss-process distributions and show preliminary comparisons to spectroscopic observations and pre-solar grains measurements.

Keywords

Cite

@article{arxiv.2004.01645,
  title  = {Modeling the formation of the $^{13}$C neutron source in AGB stars},
  author = {Diego Vescovi and Sergio Cristallo},
  journal= {arXiv preprint arXiv:2004.01645},
  year   = {2020}
}

Comments

4 pages, 2 figures, NPA IX proceedings. Accepted in JPCS