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arXiv · 0810.2494

HINODE Observations of Chromospheric Brightenings in the Ca II H Line during small-scale Flux Emergence Events

S. L. Guglielmino·F. Zuccarello·P. Romano·L. R. Bellot Rubio
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Abstract

\ion{Ca}{2} H emission is a well-known indicator of magnetic activity in the Sun and other stars. It is also viewed as an important signature of chromospheric heating. However, the \ion{Ca}{2} H line has not been used as a diagnostic of magnetic flux emergence from the solar interior. Here we report on Hinode observations of chromospheric \ion{Ca}{2} H brightenings associated with a repeated, small-scale flux emergence event. We describe this process and investigate the evolution of the magnetic flux, G-band brightness, and \ion{Ca}{2} H intensity in the emerging region. Our results suggest that energy is released in the chromosphere as a consequence of interactions between the emerging flux and the pre-existing magnetic field, in agreement with recent 3D numerical simulations.

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S. L. Guglielmino, F. Zuccarello, P. Romano, L. R. Bellot Rubio. 2008-10-15. HINODE Observations of Chromospheric Brightenings in the Ca II H Line during small-scale Flux Emergence Events. https://doi.org/10.1086/595657

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