1. Forward Asteroseismic Modeling of Stars with a Convective Core from Gravity-mode Oscillations: Parameter Estimation and Stellar Model Selection
- Author
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R. Björklund, S. Sekaran, T. Van Reeth, Kevin Truyaert, Dominic M. Bowman, Andrew Tkachenko, Péter Pápics, Cole Johnston, M. G. Pedersen, Joey S. G. Mombarg, Geert Molenberghs, B. Buysschaert, J. O. Sundqvist, E. Vermeyen, Conny Aerts, Mathias Michielsen, AERTS, Conny, MOLENBERGHS, Geert, Miechielsen, Mathias, Pedersen, M. G., Bjorklund, R., Johnston, C., Mombarg, J. S. G., Bowman, D. M., Buysschaert, B., Papics, P., I, Sekaran, S., Sundqvist, J. O., Tkachenko, A., Truyaert, K., Van Reeth, T., Vermeyen, E., Instituut voor Sterrenkunde [Leuven], Catholic University of Leuven - Katholieke Universiteit Leuven (KU Leuven), National Food Institute, Technical University of Denmark, Laboratoire de microbiologie et génétique moléculaires (LMGM), Centre de Biologie Intégrative (CBI), Université Toulouse III - Paul Sabatier (UT3), Université Fédérale Toulouse Midi-Pyrénées-Université Fédérale Toulouse Midi-Pyrénées-Centre National de la Recherche Scientifique (CNRS)-Université Toulouse III - Paul Sabatier (UT3), Université Fédérale Toulouse Midi-Pyrénées-Université Fédérale Toulouse Midi-Pyrénées-Centre National de la Recherche Scientifique (CNRS)-Centre National de la Recherche Scientifique (CNRS), Laboratoire d'études spatiales et d'instrumentation en astrophysique (LESIA (UMR_8109)), Institut national des sciences de l'Univers (INSU - CNRS)-Observatoire de Paris, Université Paris sciences et lettres (PSL)-Université Paris sciences et lettres (PSL)-Université Paris Diderot - Paris 7 (UPD7)-Sorbonne Université (SU)-Centre National de la Recherche Scientifique (CNRS), Ludwig-Maximilians-Universität München (LMU), Université Fédérale Toulouse Midi-Pyrénées-Université Fédérale Toulouse Midi-Pyrénées-Centre National de la Recherche Scientifique (CNRS), and PSL Research University (PSL)-PSL Research University (PSL)-Université Paris Diderot - Paris 7 (UPD7)-Sorbonne Université (SU)-Centre National de la Recherche Scientifique (CNRS)
- Subjects
RED-GIANT STARS ,oscillations (including pulsations) [stars] ,GAMMA DORADUS STARS ,Astronomy ,statistical [methods] ,Library science ,FOS: Physical sciences ,asteroseismology ,Astronomy & Astrophysics ,Bayesian inference ,01 natural sciences ,FAST ROTATING STARS ,FREQUENCY G-MODES ,massive [stars] ,Hospitality ,0103 physical sciences ,media_common.cataloged_instance ,Astrophysics::Solar and Stellar Astrophysics ,European union ,010303 astronomy & astrophysics ,Solar and Stellar Astrophysics (astro-ph.SR) ,ComputingMilieux_MISCELLANEOUS ,media_common ,methods: statistical ,stars: interiors ,stars: massive ,stars: oscillations (including pulsations) ,stars: rotation ,Physics ,interiors [stars] ,[PHYS]Physics [physics] ,Government ,Science & Technology ,010308 nuclear & particles physics ,business.industry ,Model selection ,Mode (statistics) ,ATMOSPHERIC NLTE-MODELS ,Astronomy and Astrophysics ,MASS-LOSS ,Advice (programming) ,INTERNAL-ROTATION ,RADIATIVE ACCELERATIONS ,Astrophysics - Solar and Stellar Astrophysics ,13. Climate action ,Space and Planetary Science ,Physical Sciences ,rotation [stars] ,Science policy ,business ,[PHYS.ASTR]Physics [physics]/Astrophysics [astro-ph] ,MAIN-SEQUENCE STARS ,NU-ERIDANI - Abstract
We propose a methodological framework to perform forward asteroseismic modeling of stars with a convective core, based on gravity-mode oscillations. These probe the near-core region in the deep stellar interior. The modeling relies on a set of observed high-precision oscillation frequencies of low-degree coherent gravity modes with long lifetimes and their observational uncertainties. Identification of the mode degree and azimuthal order is assumed to be achieved from rotational splitting and/or from period spacing patterns. This paper has two major outcomes. The first is a comprehensive list and discussion of the major uncertainties of theoretically predicted gravity-mode oscillation frequencies based on linear pulsation theory, caused by fixing choices of the input physics for evolutionary models. Guided by a hierarchy among these uncertainties of theoretical frequencies, we subsequently provide a global methodological scheme to achieve forward asteroseismic modeling. We properly take into account correlations amongst the free parameters included in stellar models. Aside from the stellar mass, metalicity and age, the major parameters to be estimated are the near-core rotation rate, the amount of convective core overshooting, and the level of chemical mixing in the radiative zones. This modeling scheme allows for maximum likelihood estimation of the stellar parameters for fixed input physics of the equilibrium models, followed by stellar model selection considering various choices of the input physics. Our approach uses the Mahalanobis distance instead of the often used $\chi^2$ statistic and includes heteroscedasticity. It provides estimation of the unknown variance of the theoretically predicted oscillation frequencies., Comment: Accepted for publication in The Astrophysical Journal Supplement Series, 45 pages, 2 tables, 18 figures
- Published
- 2018
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