Issue |
A&A
Volume 580, August 2015
|
|
---|---|---|
Article Number | A61 | |
Number of page(s) | 5 | |
Section | Stellar structure and evolution | |
DOI | https://doi.org/10.1051/0004-6361/201526294 | |
Published online | 31 July 2015 |
Toward a consistent use of overshooting parametrizations in 1D stellar evolution codes
1
Max-Planck-Institut für Astrophysik,
Karl-Schwarzschild-Str. 1,
85748
Garching,
Germany
e-mail:
mviallet@mpa-garching.mpg.de
2
Steward Observatory, 933 N. Cherry Ave., Tucson, AZ
85721,
USA
3
New Mexico Consortium, Los Alamos, NM
87544,
USA
4
Theoretical Division, Los Alamos National
Laboratory, Los Alamos,
NM
87545,
USA
Received: 10 April 2015
Accepted: 8 June 2015
Several parametrizations for overshooting in 1D stellar evolution calculations coexist in the literature. These parametrizations are used somewhat arbitrarily in stellar evolution codes, based on what works best for a given problem or even for the historical reasons related to the development of each code. We point out that these different parametrizations correspond to different physical regimes of overshooting, depending on whether the effects of radiation are dominant, marginal, or negligible. Our analysis is based on previously published theoretical results, as well as on multidimensional hydrodynamical simulations of stellar convection where the interaction between the convective region and a stably stratified region is observed. Although the underlying hydrodynamical processes are the same, the outcome of the overshooting process is profoundly affected by radiative effects. Using a simple picture of the scales involved in the overshooting process, we show how three regimes are obtained, depending on the importance of radiative effects. These three regimes correspond to the different behaviors observed in hydrodynamical simulations so far and to the three types of parametrizations used in 1D codes. We suggest that the existing parametrizations for overshooting should coexist in 1D stellar evolution codes and should be applied consistently at convective boundaries depending on the local physical conditions.
Key words: stars: evolution / stars: interiors / hydrodynamics / convection / turbulence
© ESO, 2015
Current usage metrics show cumulative count of Article Views (full-text article views including HTML views, PDF and ePub downloads, according to the available data) and Abstracts Views on Vision4Press platform.
Data correspond to usage on the plateform after 2015. The current usage metrics is available 48-96 hours after online publication and is updated daily on week days.
Initial download of the metrics may take a while.