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arXiv · 2304.13212

Exploring magnetic field properties at the boundary of solar pores: A comparative study based on SDO-HMI observations

J. I. Campos Rozo·S. Vargas Domínguez·D. Utz·A. M. Veronig·A. Hanslmeier
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Abstract

The Sun's magnetic fields play an important role in various solar phenomena. Solar pores are regions of intensified magnetic field strength compared to the surrounding photospheric environment, and their study can help us better understand the properties and behaviour of magnetic fields in the Sun. Up to now, there exists only a single study on magnetic field properties at the boundary region of a pore. Therefore, the main goal of this work is to increase the statistics of magnetic properties determining the pore boundary region. We analyse six solar pores using data from the Helioseismic and Magnetic Imager instrument on board the Solar Dynamics Observatory. We apply image processing techniques to extract the relevant features of the solar pores and determine the boundary conditions of the magnetic fields. We find the maximal vertical magnetic field values on the boundaries of the studied solar pores to range from 1400~G to 1600~G, with a standard deviation between 7.8\% and 14.8\%. These values are lower than those reported in the mentioned preceding study. However, this can be explained by differences in spatial resolution as well as the type of data we used. The vertical magnetic field is an important factor in determining the boundary of solar pores, and it plays a more relevant role than the intensity gradient. The obtained information will be useful for future studies on the formation and evolution of magnetic structures of the Sun. Additionally, this study highlights the importance of high spatial resolution data for the purpose of accurately characterising the magnetic properties of solar pores.

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J. I. Campos Rozo, S. Vargas Domínguez, D. Utz, A. M. Veronig, A. Hanslmeier. 2023-04-26. Exploring magnetic field properties at the boundary of solar pores: A comparative study based on SDO-HMI observations. https://doi.org/10.1051/0004-6361%2F202346389

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