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Detección de flujos descendentes convectivos en la penumbra de una mancha solar

G B Scharmer¹, V M J Henriques, D Kiselman

¹Institute for Solar Physics of the Royal Swedish Academy of Sciences, and Department of Astronomy at Stockholm University, AlbaNova University Center, SE-10691 Stockholm, Sweden. scharmer@astro.su.se

Science (New York, N.Y.)

|June 4, 2011

Resumen

Los astrónomos observaron flujos oscuros y descendentes en las penumbras de las manchas solares, revelando un patrón de convección. Este descubrimiento explica el flujo de Evershed como la parte horizontal de esta convección solar recién identificada.

Área de la Ciencia:

Física solar Física solar es la física de la energía solar.
La astrofísica del plasma es la astrofísica del plasma.
La dinámica estelar es la dinámica estelar.

Sus antecedentes:

Las manchas solares y su penumbra externa han desconcertado durante mucho tiempo a los astrónomos con respecto a su estructura y dinámica.
Modelos teóricos y simulaciones previas sugirieron la convección de volcado como una explicación para los filamentos penumbrales y la salida de energía.

Objetivo del estudio:

Para investigar la estructura fina y la dinámica de las penumbras de manchas solares.
Para detectar y caracterizar los flujos descendentes dentro de la penumbra.
Para entender la relación entre estos flujos y el flujo de Evershed.

Principales métodos:

Se utilizaron datos espectropolarimétricos de imágenes del Telescopio Solar Sueco de 1 metro.
Análisis de datos para detectar y medir las velocidades de flujo en la penumbra solar.

Principales resultados:

Se detectaron flujos descendentes ubicuos y relativamente oscuros de hasta 1 km/s en el interior de la penumbra.
Estos flujos descendentes son distintos de los flujos en tubos de flujo arqueados y son omnipresentes.
Se observaron fuertes salidas radiales (3 a 3.5 km/s) asociadas con los flujos descendentes.

Conclusiones:

Los flujos descendentes detectados son parte de un patrón de flujo convectivo penumbral.
El flujo de Evershed se identifica como el componente horizontal de esta convección penumbral.
Este hallazgo proporciona una nueva comprensión del transporte de energía y la dinámica dentro de las manchas solares.

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