Coronal heating and solar wind formation in quiet Sun and coronal holes: a unified scenario

Abstract

Coronal holes (CHs) are darker than quiet Sun (QS) when observed in coronal channels. This study aims to understand the similarities and differences between CHs and QS in the transition region using the \ion{Si}{4}~1394~Å line recorded by the Interface Region Imaging Spectrograph (IRIS) by considering the distribution of magnetic field measured by the Helioseismic and Magnetic Imager (HMI) onboard the Solar Dynamics Observatory (SDO). We find that \ion{Si}{4} intensities obtained in CHs are lower than those obtained in QS for regions with identical magnetic flux densities. Moreover, the difference in intensities between CHs and QS increases with increasing magnetic flux. For the regions with equal magnetic flux density, QS line profiles are more redshifted than those measured in CHs. Moreover, the blue shifts measured in CHs show an increase with increasing magnetic flux density unlike in the QS. The non-thermal velocities in QS, as well as in CHs, show an increase with increasing magnetic flux. However, no significant difference was observed in QS and CHs, albeit a small deviation at small flux densities. Using these results, we propose a unified model for the heating of the corona in the QS and in CHs and the formation of the solar wind.

ApJ, in press, 26 pages, 5 figures and 12 figures in appendix

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Cited by in corpus (9)

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• Coronal Heating and Solar Wind Generation by Flux Cancellation Reconnection
• On the Impulsive Heating of Quiet Solar Corona
• Synchronization of Small-scale Magnetic Features, Blinkers, and Coronal Bright Points
• Nanoflare Heating of the Solar Corona Observed in X-rays
• Asymmetry of the spectral lines of the coronal hole and quiet Sun in the transition region
• Heating in the Solar Atmosphere at a Fin Current Sheet Driven by Magnetic Flux Cancellation