Simulación Numérica de Procesos Astrofísicos

Año de inicio
2003
Unidad organizativa
    General
    Descripción

    La simulación numérica mediante códigos complejos de ordenador es una herramienta fundamental en la investigación física y en la técnica desde hace décadas. El crecimiento vertiginoso de las capacidades informáticas junto con el avance notable de la matemática numérica ha hecho accesible a los centros de investigación de tamaño medio esta rama de la investigación, a caballo entre la física teórica y la física experimental. La astrofísica no es excepción a lo anterior, habiéndose desarrollado desde finales de los 70 una especialidad de la misma, la astrofísica computacional, que ha permitido llegar a comprender gran variedad de fenómenos inaccesibles a la investigación teórica pura y dar cuenta de observaciones hasta entonces inexplicadas. Su mayor campo de aplicación en las décadas pasadas han sido los fenómenos (magneto) hidrodinámicos y de dinámica de gases en multiplicidad de entornos cósmicos, por ejemplo los interiores y atmósferas estelares y planetarios y el medio interestelar, incluyendo magnetoconvección y dínamo, discos de acreción, evolución de nebulosas planetarias, explosiones y restos de supernova, etc. La incorporación a las simulaciones numéricas de las ecuaciones del transporte radiativo, ocurrida ya en décadas pasadas, ha permitido dotar de mayor realismo a los estudios de procesos hidrodinámicos en fotosferas y cromosferas estelares.

    El presente Proyecto quiere apoyar el desarrollo en el IAC de la investigación astrofísica basada en el uso de grandes códigos numéricos que requieren el uso de ordenadores masivamente paralelos y su enlace con los resultados de observación. Objetivo general de este Proyecto es la realización de cálculos de física de fluidos cósmicos y de transporte radiativo. La temática de dichos cálculos se centrará en

    • fenómenos de dinámica de gases magnetizados en interiores y atmósferas estelares
    • transporte de radiación y señales de polarización en líneas espectrales en base a modelos atómicos y moleculares realistas y los efectos Hanle y Zeeman
    • comparación de resultados teórico/numéricos con datos de observación

    Este Proyecto es especialmente relevante a la vista de la involucración, cada vez mayor, del IAC en las redes de supercomputación nacionales y europeas y, en general, en grandes iniciativas de instalación de superordenadores.

    1. En las regiones del Sol en calma se observan diminutos lazos magnéticos emerger del interior de gránulos. Mediante simulaciones numéricas 3D se ha descubierto el proceso de formación de estas estructuras. Los resultados han sido publicados en el trabajo ApJ Letter 859, id. L26 liderado por Prof Fernando Moreno-Insertis.
    2. En una colaboración internacional se han catalogado casi 200 oscilaciones en protuberancias solares. Este es el primer estudio estadístico que se hace de estos eventos incluyendo una gran cantidad de oscilaciones de gran amplitud. El trabajo ha sido liderado por Dr Manuel Luna y publicado en ApJ Supplement Series, 236, id. 35.

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