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Variaciones dinámicas en la base de la zona de convección solar
Howe1, Christensen-Dalsgaard, Hill
1National Solar Observatory, National Optical Astronomy Observatories, Post Office Box 26732, Tucson, AZ 85726-6732, USA. Theoretical Astrophysics Center, Danish National Research Foundation, and Institute of Physics and Astronomy, Aarhus Uni.
Science (New York, N.Y.)
|March 31, 2000
Resumen
Los científicos observaron cambios en la rotación del Sol cerca de su base, revelando una variación de 1,3 años en latitudes bajas. Estos hallazgos ofrecen información sobre la dínamo solar, lo que podría explicar los ciclos de actividad magnética del Sol.
Área de la Ciencia:
- Física solar Física solar es la física de la energía solar.
- Seismología helioseismológica.
- La astrofísica es la astrofísica.
Sus antecedentes:
- La rotación interna del Sol influye en sus ciclos de actividad magnética.
- Comprender la dinámica de rotación es clave para modelar la dinamo solar.
- Estudios anteriores carecían de mediciones detalladas de la rotación profunda del interior solar.
Objetivo del estudio:
- Para detectar y cuantificar los cambios temporales en la rotación interna del Sol.
- Para investigar las variaciones de rotación cerca de la tacoclina, el límite entre las zonas de convección y radiativa.
- Para explorar el vínculo entre los cambios de rotación interna y la dinamo solar.
Principales métodos:
- Utilizando sondeo heliosísmico a través de la observación casi continua de los modos de oscilación solar.
- Empleando dos configuraciones experimentales complementarias para la adquisición de datos.
- Invertir las divisiones de frecuencia de modo global para determinar la velocidad angular (Omega).
Principales resultados:
- Se detectaron cambios temporales significativos en la rotación solar (hasta 6 nHz) cerca de la base de la envoltura convectiva.
- Se observó una prominente variación en el período de 1,3 años en la rotación en latitudes bajas.
- Se encontraron cambios de rotación más pronunciados cerca del ecuador y latitudes altas, por encima y por debajo de la tacoclina.
Conclusiones:
- Las variaciones de rotación detectadas ocurren cerca del sitio presunto de la dinamo solar.
- Estos cambios son sustanciales en relación con el gradiente radial en la velocidad angular a través de la tacoclina.
- Los hallazgos sugieren una conexión entre la dinámica de rotación interna y la generación de los ciclos de actividad magnética de 22 años del Sol.
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