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arXiv · 1902.03764

Association of calcium network bright points with underneath photospheric magnetic patches

Nancy Narang·Dipankar Banerjee·Kalugodu Chandrashekhar·Vaibhav Pant
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Abstract

Recent dedicated Hinode polar region campaigns revealed the presence of concentrated kilogauss patches of magnetic field in the polar regions of the Sun which are also shown to be correlated with facular bright points at the photospheric level. In this work, we demonstrate that this spatial intermittency of the magnetic field persists even up to the chromospheric heights. The small-scale bright elements visible in the bright network lanes of solar network structure as seen in the Ca ii H images are termed as network bright points. We use special Hinode campaigns devoted to observe polar regions of the Sun to study the polar network bright points during the phase of last extended solar minimum. We use Ca ii H images of chromosphere observed by Solar Optical Telescope (SOT). For magnetic field information, level 2 data of spectro-polarimeter (SP) is used. We observe a considerable association between the polar network bright points and magnetic field concentrations. The intensity of such bright points is found to be correlated well with the photospheric magnetic field strength underneath with a linear relation existing between them.

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Nancy Narang, Dipankar Banerjee, Kalugodu Chandrashekhar, Vaibhav Pant. 2019-02-11. Association of calcium network bright points with underneath photospheric magnetic patches. https://doi.org/10.1007/s11207-019-1419-5

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