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arXiv · 1009.4795

Detection of large acoustic energy flux in the solar atmosphere

N. Bello González·M. Franz·V. Martínez Pillet·J. A. Bonet·S. K. Solanki·J. C. del Toro Iniesta·W. Schmidt·A. Gandorfer·V. Domingo·P. Barthol·T. Berkefeld·M. Knölker
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Abstract

We study the energy flux carried by acoustic waves excited by convective motions at sub-photospheric levels. The analysis of high-resolution spectropolarimetric data taken with IMaX/Sunrise provides a total energy flux of ~ 6400--7700 Wm$^{-2}$ at a height of ~ 250 km in the 5.2-10 mHz range, i.e. at least twice the largest energy flux found in previous works. Our estimate lies within a factor of 2 of the energy flux needed to balance radiative losses from the chromosphere according to Anderson & Athay (1989) and revives interest in acoustic waves for transporting energy to the chromosphere. The acoustic flux is mainly found in the intergranular lanes but also in small rapidly-evolving granules and at the bright borders, forming dark dots and lanes of splitting granules.

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N. Bello González, M. Franz, V. Martínez Pillet, J. A. Bonet, S. K. Solanki, J. C. del Toro Iniesta, W. Schmidt, A. Gandorfer, V. Domingo, P. Barthol, T. Berkefeld, M. Knölker. 2010-09-24. Detection of large acoustic energy flux in the solar atmosphere. https://doi.org/10.1088/2041-8205%2F723%2F2%2Fl134

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