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Title: Coronal bright points associated with minifilament eruptions

Coronal bright points (CBPs) are small-scale, long-lived coronal brightenings that always correspond to photospheric network magnetic features of opposite polarity. In this paper, we subjectively adopt 30 CBPs in a coronal hole to study their eruptive behavior using data from the Atmospheric Imaging Assembly (AIA) and the Helioseismic and Magnetic Imager (HMI) on board the Solar Dynamics Observatory. About one-quarter to one-third of the CBPs in the coronal hole go through one or more minifilament eruption(s) (MFE(s)) throughout their lifetimes. The MFEs occur in temporal association with the brightness maxima of CBPs and possibly result from the convergence and cancellation of underlying magnetic dipoles. Two examples of CBPs with MFEs are analyzed in detail, where minifilaments appear as dark features of a cool channel that divide the CBPs along the neutral lines of the dipoles beneath. The MFEs show the typical rising movements of filaments and mass ejections with brightenings at CBPs, similar to large-scale filament eruptions. Via differential emission measure analysis, it is found that CBPs are heated dramatically by their MFEs and the ejected plasmas in the MFEs have average temperatures close to the pre-eruption BP plasmas and electron densities typically near 10{sup 9} cm{sup –3}. These newmore » observational results indicate that CBPs are more complex in dynamical evolution and magnetic structure than previously thought.« less
Authors:
; ; ; ;  [1] ; ;  [2]
  1. Yunnan Observatories, Chinese Academy of Sciences, Kunming 650011 (China)
  2. Also at Graduate School of Chinese Academy of Sciences, Beijing, China. (China)
Publication Date:
OSTI Identifier:
22370183
Resource Type:
Journal Article
Resource Relation:
Journal Name: Astrophysical Journal; Journal Volume: 796; Journal Issue: 2; Other Information: Country of input: International Atomic Energy Agency (IAEA)
Country of Publication:
United States
Language:
English
Subject:
79 ASTROPHYSICS, COSMOLOGY AND ASTRONOMY; BORON PHOSPHIDES; BRIGHTNESS; CANCELLATION; DIPOLES; ELECTRON DENSITY; EMISSION; ERUPTION; EVOLUTION; FILAMENTS; MASS; PLASMA; STELLAR CORONAE; SUN