Constraining Extra Mixing During the Main Sequence: Whatever Depletes Lithium Does Not Touch Beryllium
Creators
-
1.
Gemini South Observatory
-
2.
Carnegie Observatories
-
3.
Laboratório Nacional de Astrofísica
-
4.
California Institute of Technology
-
5.
National University of San Marcos
-
6.
Pontificia Universidad Católica de Chile
Abstract
Measurements of lithium (Li) abundances in solar-type stars have shown that standard models of stellar evolution are incapable of explaining the observed depletion as a function of stellar age. Beryllium (Be) is one of the lightest elements that can be measured in stellar photospheres and can be burned at relatively low temperatures. Studying its abundances as a function of stellar age can provide important constraints to stellar mixing models because the level of depletion as a function of time will indicate how deep the photospheric material must be dredged to explain the observed abundances. In an effort to provide the most stringent constraints for nonstandard stellar mixing models, we observed a sample of solar twins and concomitantly analyzed their Li and Be abundances. Unlike what is typically observed for Li, we found that Be does not decrease as a function of stellar age along the main sequence, constraining models that predict the burning of both materials. Based on our data, models that invoke convective overshoot and convective settling are preferred over typical rotationally induced mixing models, as the later burn Be in excess while the former do not. Previous works also proposed mixing due to gravity waves as a possible explanation for observed abundances, which can fit our data as well. Furthermore, based on our solar twins, Be depletion likely happens within the first ∼1 Gyr. We also confirm previous findings of an increase in Be abundance as a function of metallicity, indicative of galactic production via cosmic-ray spallation.
Copyright and License
© 2025. The Author(s). Published by the American Astronomical Society.
Original content from this work may be used under the terms of the Creative Commons Attribution 4.0 licence. Any further distribution of this work must maintain attribution to the author(s) and the title of the work, journal citation and DOI.
Acknowledgement
H.R. acknowledges the support from NOIRLab, which is managed by the Association of Universities for Research in Astronomy (AURA) under a cooperative agreement with the National Science Foundation. J.Y.G. acknowledges support from a Carnegie Fellowship. D.L.-O. acknowledges the support from CNPq (PCI 301612/2024-2). S.C. acknowledges support from the Carnegie Astrophysics Summer Student Internship Program (CASSI) and the Ralph M. Parsons Foundation. J.C. acknowledges support from the Agencia Nacional de Investigación y Desarrollo (ANID) via Proyecto Fondecyt Regular 1231345, and from ANID BASAL project CATA2-FB210003. The authors would like to thank the referee for their contribution in increasing the quality of the published version of the paper. The authors also thank Joshua D. Simon and Andrew McWilliam for the useful discussions about this project.
Facilities
VLT:Kueyen - Very Large Telescope (Kueyen), ESO:3.6m - European Southern Observatory's 3.6 meter Telescope, Gaia - .
Software References
numpy (S. van der Walt et al. 2011), matplotlib (J. D. Hunter 2007), pandas (W. McKinney 2010), iraf (D. Tody 1986), iSpec (S. Blanco-Cuaresma et al. 2014; S. Blanco-Cuaresma 2019), Kapteyn Package (J. P. Terlouw & M. G. R. Vogelaar 2016), moog (C. A. Sneden 1973), q2 (I. Ramírez et al. 2014).
Additional Information
Based on observations collected at the European Southern Observatory under ESO programme 111.24VX.
Files
Reggiani_2025_ApJ_984_108.pdf
Files
(734.1 kB)
| Name | Size | Download all |
|---|---|---|
|
md5:e59f848a18e35227b8336dafeaad1b3b
|
734.1 kB | Preview Download |
Additional details
Related works
- Is new version of
- Discussion Paper: arXiv:2408.10999 (arXiv)
Funding
- NSF's NOIRLab
- Conselho Nacional de Desenvolvimento Científico e Tecnológico
- PCI 301612/2024-2
- Carnegie Institution for Science
- Ralph M. Parsons Foundation
- Agencia Nacional de Investigación y Desarrollo
- 1231345
- Agencia Nacional de Investigación y Desarrollo
- CATA2-FB210003
Dates
- Accepted
-
2025-03-18
- Available
-
2025-05-02Published