stars: oscillations; stars: atmospheres; stars: variables: general
Abstract :
[en] We present an improved version of the method of photometric mode identification of Heynderickx et al. (\cite{hey}). Our new version is based on the inclusion of precise non-adiabatic eigenfunctions determined in the outer stellar atmosphere according to the formalism recently proposed by Dupret et al. (\cite{dup}). Our improved photometric mode identification technique is therefore no longer dependent on ad hoc parameters for the non-adiabatic effects. It contains the complete physical conditions of the outer atmosphere of the star, provided that rotation does not play a key role. We apply our method to the two slowly pulsating B stars HD 74560 and HD 138764 and to the beta Cephei star EN (16) Lac. Besides identifying the degree l of the pulsating stars, our method is also a tool for improving the knowledge of stellar interiors and atmospheres, by imposing constraints on parameters such as the metallicity and the mixing-length parameter alpha (a procedure we label non-adiabatic asteroseismology). The non-adiabatic eigenfunctions needed for the mode identification are available upon request from the authors.
Disciplines :
Space science, astronomy & astrophysics
Author, co-author :
Dupret, Marc-Antoine ; Université de Liège - ULiège > Département d'astrophys., géophysique et océanographie (AGO) > Astrophysique stellaire théorique
De Ridder, J.; Instituut voor Sterrenkunde, Katholieke Universiteit Leuven, Celestijnenlaan 200, 3001 Leuven, Belgium
De Cat, P.; Instituut voor Sterrenkunde, Katholieke Universiteit Leuven, Celestijnenlaan 200, 3001 Leuven, Belgium
Aerts, C.; Instituut voor Sterrenkunde, Katholieke Universiteit Leuven, Celestijnenlaan 200, 3001 Leuven, Belgium
Scuflaire, Richard ; Université de Liège - ULiège > Département d'astrophys., géophysique et océanographie (AGO) > Evol. et stabilité des étoiles et des amas d'étoiles (ESEA)
Noels-Grötsch, Arlette ; Université de Liège - ULiège > Département d'astrophys., géophysique et océanographie (AGO) > Département d'astrophys., géophysique et océanographie (AGO)
Thoul, Anne ; Université de Liège - ULiège > Département d'astrophys., géophysique et océanographie (AGO) > Evol. et stabilité des étoiles et des amas d'étoiles (ESEA)
Language :
English
Title :
A photometric mode identification method, including an improved non-adiabatic treatment of the atmosphere
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