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La supresión del enfriamiento por fuertes campos magnéticos en estrellas enanas blancas
G Valyavin1, D Shulyak2, G A Wade3
1Special Astrophysical Observatory of Russian Academy of Science, Nizhnij Arkhyz, Zelenchukskiy region, Karachai-Cherkessian Republic 369167, Russia.
Nature
|October 21, 2014
Resumen
Las estrellas enanas blancas frías con fuertes campos magnéticos parecen más jóvenes debido al enfriamiento suprimido. Este efecto de campo magnético explica por qué las enanas blancas más viejas y frías suelen exhibir campos fuertes, resolviendo un rompecabezas astronómico de larga data.
Área de la Ciencia:
- La astronomía es la astronomía.
- La astrofísica estelar es la astrofísica estelar.
- La magnetohidrodinámica es una dinámica magnético-hidrodinámica.
Sus antecedentes:
- Las enanas blancas frías a menudo poseen fuertes campos magnéticos, contrariamente a las expectativas de descomposición del campo con el tiempo.
- Las variaciones de brillo en las enanas blancas magnéticas se atribuyen a las inhomogeneidades superficiales y a los efectos magneto-ópticos.
Objetivo del estudio:
- Para investigar la relación entre los campos magnéticos y las propiedades atmosféricas en enanas blancas frías.
- Para explicar la prevalencia de fuertes campos magnéticos en las estrellas enanas blancas más frías.
Principales métodos:
- Observaciones ópticas a largo plazo del brillo y el campo magnético de la enana blanca WD 1953-011.11.
- Análisis de la temperatura de la superficie y la distribución del campo magnético.
Principales resultados:
- Los fuertes campos magnéticos suprimen la convección atmosférica en las enanas blancas.
- La convección suprimida conduce a manchas oscuras en regiones altamente magnetizadas.
- Los campos magnéticos inhiben la evolución del enfriamiento de las enanas blancas frías.
Conclusiones:
- La supresión del campo magnético de la convección explica la prevalencia de campos fuertes en las enanas blancas frías.
- Este mecanismo hace que las enanas blancas fuertemente magnéticas parezcan más jóvenes que su edad real.
- Las estimaciones actuales de la edad de las enanas blancas fuertemente magnéticas pueden estar sistemáticamente subestimadas.
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