2018/02/16 by Adam S. Jermyn, Mihkel Kama
Physics and Astronomy · #Accretion (finance) #Astro and Planetary Science #Astronomy #Astrophysics #Astrophysics and Star Formation Studies #Photosphere #Physics #Planet #Planetary system #Protoplanetary disk #Radiative transfer #Spectral line #Stars #Stellar, planetary, and galactic studies #astro-ph.EP #astro-ph.SR
paper · pdf · doi:10.1093/mnras/sty429
published as Monthly Notices of the Royal Astronomical Society, Volume 476, Issue 4, 1 June 2018, Pages 4418-4434 · 17 pages, 9 figures. Published in MNRAS. Updated with discussion of WD pollution
openalex publication_date 2018/02/16 · openalex created_date 2018/03/29 · arxiv created 2018/05/03 · arxiv updated 2018/05/07 · openalex updated_date 2026/08/05
Protoplanetary discs, debris discs, and disrupted or evaporating planets can all feed accretion on to stars. The photospheric abundances of such stars may then reveal the composition of the accreted material. This is especially likely in B to mid-F type stars, which have radiative envelopes and hence less bulk-photosphere mixing. We present a theoretical framework (CAM), considering diffusion, rotation, and other stellar mixing mechanisms to describe how the accreted material interacts with the bulk of the star. This allows the abundance pattern of the circumstellar material to be calculated from measured stellar abundances and parameters (vrot, Teff). We discuss the λ Boötis phenomenon and the application of CAM on stars hosting protoplanetary discs (HD 100546, HD 163296), debris discs (HD 141569, HD 21997), and evaporating planets (HD 195689/KELT-9).