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Asteroseismología de HD 129929: rebasamiento del núcleo y rotación no rígida
C Aerts1, A Thoul, J Daszynska
1Instituut voor Sterrenkunde, Katholieke Universiteit Leuven, Celestijnenlaan 200 B, B-3001 Leuven, Belgium. conny@ster.kuleuven.ac.be
Science (New York, N.Y.)
|May 31, 2003
Resumen
Este estudio analizó 21 años de datos fotométricos de la estrella B3V HD 129929, revelando una rotación lenta y un exceso de convección del núcleo. Las restricciones de metalicidad se alinean con los hallazgos espectroscópicos, descartando la rotación rígida.
Área de la Ciencia:
- Asteroseismología La Asteroseismología
- La astrofísica estelar es la astrofísica estelar.
- La fotometría es la fotometría.
Sus antecedentes:
- HD 129929 es una estrella B3V.
- Los datos fotométricos a largo plazo son cruciales para comprender las propiedades estelares.
Objetivo del estudio:
- Analizar 21 años de datos fotométricos de Ginebra para HD 129929.9.
- Determinar las propiedades estelares como la velocidad de rotación, la metalicidad y la estructura interna.
Principales métodos:
- Recopiló y analizó 1493 observaciones fotométricas multicolores.
- Se detectaron seis frecuencias dominantes.
- Se realizó un análisis de oscilación no adiabático.
Principales resultados:
- Se detectó una división rotacional con un intervalo de ~0.0121 ciclos por día, lo que indica una rotación lenta.
- Metalicidad restringida a Z = [0.017, 0.022], consistente con los datos espectroscópicos.
- Proporcionó evidencia para el sobrevuelo convectivo del núcleo (alfa) = 0.10 +/- 0.05).
- Se descartó la rotación rígida.
Conclusiones:
- HD 129929 exhibe una rotación lenta y una sobrecarga convectiva del núcleo.
- El análisis asterosísmico proporciona restricciones confiables sobre la metalicidad estelar y la física interna.
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