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arXiv · 1906.07687

The magnetic properties of photospheric magnetic bright points with high resolution spectropolarimetry

Peter H. Keys·Aaron Reid·Mihalis Mathioudakis·Sergiy Shelyag·Vasco M. J. Henriques·Rebecca L. Hewitt·Dario Del Moro·Shahin Jafarzadeh·David B. Jess·Marco Stangalini
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Abstract

Magnetic bright points are small-scale magnetic elements ubiquitous across the solar disk, with the prevailing theory suggesting that they form due to the process of convective collapse. Employing a unique full Stokes spectropolarimetric data set of a quiet Sun region close to disk centre obtained with the Swedish Solar Telescope, we look at general trends in the properties of magnetic bright points. In total we track 300 MBPs in the data set and we employ NICOLE inversions to ascertain various parameters for the bright points such as line-of-sight magnetic field strength and line-of-sight velocity, for comparison. We observe a bimodal distribution in terms of maximum magnetic field strength in the bright points with peaks at ~480 G and ~1700 G, although we cannot attribute the kilogauss fields in this distribution solely to the process of convective collapse. Analysis of MURaM simulations does not return the same bimodal distribution. However, the simulations provide strong evidence that the emergence of new flux and diffusion of this new flux play a significant role in generating the weak bright point distribution seen in our observations.

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Peter H. Keys, Aaron Reid, Mihalis Mathioudakis, Sergiy Shelyag, Vasco M. J. Henriques, Rebecca L. Hewitt, Dario Del Moro, Shahin Jafarzadeh, David B. Jess, Marco Stangalini. 2019-06-18. The magnetic properties of photospheric magnetic bright points with high resolution spectropolarimetry. https://doi.org/10.1093/mnrasl%2Fslz097

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