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arXiv · 2103.16824

On the Impulsive Heating of Quiet Solar Corona

Vishal Upendran·Durgesh Tripathi
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Abstract

The solar corona consists of a million-degree Kelvin plasma. A complete understanding of this phenomenon demands the study of Quiet Sun (QS) regions. In this work, we study QS regions in the 171 {\AA}, 193 {\AA} and 211 {\AA} passbands of the Atmospheric Imaging Assembly (AIA) on board the Solar Dynamics Observatory (SDO), by combining the empirical impulsive heating forward model of Pauluhn & Solanki (2007) with a machine-learning inversion model that allows uncertainty quantification. We find that there are {\approx} 2--3 impulsive events per min, with a lifetime of about 10--20 min. Moreover, for all the three passbands, the distribution of power law slope {\alpha} peaks above 2. Our exploration of correlations among the frequency of impulsive events and their timescales and peak energy suggests that conduction losses dominate over radiative cooling losses. All these finding suggest that impulsive heating is a viable heating mechanism in QS corona.

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Vishal Upendran, Durgesh Tripathi. 2021-03-31. On the Impulsive Heating of Quiet Solar Corona. https://doi.org/10.3847/1538-4357%2Fabf65a

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