Magnestismo Solar y Estelar

    General
    Descripción

    Los campos magnéticos son uno de los ingredientes fundamentales en la formación de estrellas y su evolución. En el nacimiento de una estrella, los campos magnéticos llegan a frenar su rotación durante el colapso de la nube molecular, y en el fin de la vida de una estrella, el magnetismo puede ser clave en la forma en la que se pierden las capas externas de forma dramática. En la vida adulta, el magnetismo da lugar a la actividad de las estrellas. Nuestro Sol tiene campos magnéticos que dan lugar a una actividad tan espectacular que es capaz de tener un impacto en la Tierra. Pero en otras estrellas, la actividad magnética es, en algunos casos, órdenes de magnitud más intensa que la solar, influenciando drásticamente el transporte de especies químicas y de momento angular, así como afectando posibles sistemas planetarios alrededor de éstas.

    La finalidad de este Proyecto es estudiar diversas manifestaciones del campo magnético que se pueden observar en la atmosfera solar y en otras estrellas. Estas incluyen estructuras tan diversas como las manchas solares, los campos débiles presentes en el sol en calma o estructuras cromosféricas y coronales como los filamentos y las protuberancias. Así, se han ido abordando gradualmente los siguientes temas de investigación:

     

    Magnetismo solar

    1. Estructura y evolución del campo magnético en manchas solares.
    2. Estructura y evolución del campo magnético en el Sol en calma.
    3. Estructura y evolución del campo magnético en la cromosfera y en estructuras cromosféricas (protuberancias, espículas,...)
    4. Estructura y evolución del campo magnético en bucles coronales.
    5. Estructura y evolución del campo magnético global del Sol. Estudios del ciclo de actividad magnética.
    6. Estudio empírico de la propagación de ondas magnetohidrodinámicas en el seno de estructuras magnéticas.
    7. Estudio empírico de mecanismos relacionados con el calentamiento de las capas externas del Sol.
    8. Estudio empírico de la influencia de la ionización parcial en la dinamica de la atmosfera solar.
    9. Implicación en el proyecto del Telescopio Solar Europeo.

    Magnetismo estelar

    1. Desarrollo de métodos numéricos para el diagnóstico del campo magnético estelar, tanto en la superficie como en la cromosfera.
    2. Estudio del magnetismo en protuberancias estelares.
    3. Impacto del campo magnético en las últimas fases de la evolución estelar.
    Investigador principal
    Personal del proyecto
    1. Ondas espirales en manchas solares: Se han interpretado como ondas magnetoacústicas que se propagan desde el interior hasta capas atmosféricas siguiendo la dirección del campo magnético. Se ha caracterizado la topología del campo magnético de la mancha, descartando que la forma espiral sea consecuencia del retorcimiento de las líneas de campo (Felipe et al. 2019).
    2. Respuesta magnética a umbral flashes: Observaciones espectropolarimétricas simultáneas de las líneas cromosféricas He I 10830 y Ca II 8542 fueron usadas para estimar las fluctuaciones del campo magnético asociado a ondas de choque. Los choques provocan la expansión de las líneas de campo (Houston et al. 2018, incluye a A. Asensio Ramos).

    Publicaciones relacionadas

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      Fecha de publicación:

      12
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      11
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    • Multiple Stokes I inversions for inferring magnetic fields in the spectral range around Cr I 5782 Å

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      10
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    • Diagnostic capabilities of spectropolarimetric observations for understanding solar phenomena. I. Zeeman-sensitive photospheric lines

      Future ground-based telescopes will expand our capabilities for simultaneous multi-line polarimetric observations in a wide range of wavelengths, from the near-ultraviolet to the near-infrared. This creates a strong demand to compare candidate spectral lines to establish a guideline of the lines that are most appropriate for each observation target

      Quintero Noda, C. et al.

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      8
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    • Constraining the magnetic vector in the quiet solar photosphere and the impact of instrumental degradation

      Context. With the advent of next generation high resolution telescopes, our understanding of how the magnetic field is organized in the internetwork (IN) photosphere is likely to advance significantly. Aims: We aim to evaluate the extent to which we can retrieve accurate information about the magnetic vector in the IN photosphere using inversion

      Campbell, R. J. et al.

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      10
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    • Limitations of the Ca II 8542 Å Line for the Determination of Magnetic Field Oscillations

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      Felipe, Tobias et al.

      Fecha de publicación:

      9
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    • Performance of solar far-side active region neural detection

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      Fecha de publicación:

      8
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    • Exploring the Sun's upper atmosphere with neural networks: Reversed patterns and the hot wall effect

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      Socas-Navarro, H. et al.

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    • Two-fluid simulations of Rayleigh-Taylor instability in a magnetized solar prominence thread. II. Effects of collisionality

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      6
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      Arregui, Iñigo

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    • Machine learning initialization to accelerate Stokes profile inversions

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    • Mapping the Hidden Magnetic Field of the Quiet Sun

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      Trelles Arjona, J. C. et al.

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      7
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    • Chromospheric Heating by Magnetohydrodynamic Waves and Instabilities

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      Srivastava, A. K. et al.

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      Fecha de publicación:

      6
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    • Probing Uncertainties in Diagnostics of a Synthetic Chromosphere

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      5
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      Abia, C. et al.

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    • Critical Science Plan for the Daniel K. Inouye Solar Telescope (DKIST)

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      Rast, Mark P. et al.

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