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Title: EXTREMELY LARGE EUV LATE PHASE OF SOLAR FLARES

Abstract

The second peak in the Fe xvi 33.5 nm line irradiance observed during solar flares by the Extreme-Ultraviolet Variability Experiment (EVE) is known as the EUV late phase. Our previous paper in 2013 by Liu et al. found that the main emissions in the late phase are originated from large-scale loop arcades that are closely connected to but different from the post-flare loops (PFLs), and we also proposed that a long cooling process without additional heating could explain the late phase. In this paper, we define the extremely large late phase because it not only has a bigger peak in the warm 33.5 irradiance profile, but also releases more EUV radiative energy than the main phase. Through detailed inspection of the EUV images from three points of view, it was discovered that aside from the later-phase loop arcades, the main contributor of the extremely large late phase is a hot structure that fails to erupt. This hot structure is identified as a flux rope, which is quickly energized by the flare reconnection and later on continuously produces the thermal energy during the gradual phase. Together with the late-phase loop arcades, the flux rope failing to erupt with the additional heatingmore » create the extremely large EUV late phase.« less

Authors:
; ; ;  [1];  [2];  [3]
  1. Key Laboratory of Geospace Environment, University of Science and Technology of China, No. 96 Jinzhai Road, Hefei, Anhui Province 230026 (China)
  2. School of Physics, Astronomy and Computational Sciences, George Mason University, 4400 University Drive, MSN 6A2, Fairfax, VA 22030 (United States)
  3. School of Astronomy and Space Science, Nanjing University, Nanjing 210093 (China)
Publication Date:
OSTI Identifier:
22522033
Resource Type:
Journal Article
Resource Relation:
Journal Name: Astrophysical Journal; Journal Volume: 802; Journal Issue: 1; Other Information: Country of input: International Atomic Energy Agency (IAEA)
Country of Publication:
United States
Language:
English
Subject:
79 ASTROPHYSICS, COSMOLOGY AND ASTRONOMY; EXTREME ULTRAVIOLET RADIATION; HEATING; IMAGES; MAGNETIC FLUX; RADIANT FLUX DENSITY; SOLAR FLARES; SUN

Citation Formats

Liu, Kai, Wang, Yuming, Liu, Rui, Shen, Chenglong, Zhang, Jie, and Cheng, Xin, E-mail: kailiu@mail.ustc.edu.cn. EXTREMELY LARGE EUV LATE PHASE OF SOLAR FLARES. United States: N. p., 2015. Web. doi:10.1088/0004-637X/802/1/35.
Liu, Kai, Wang, Yuming, Liu, Rui, Shen, Chenglong, Zhang, Jie, & Cheng, Xin, E-mail: kailiu@mail.ustc.edu.cn. EXTREMELY LARGE EUV LATE PHASE OF SOLAR FLARES. United States. doi:10.1088/0004-637X/802/1/35.
Liu, Kai, Wang, Yuming, Liu, Rui, Shen, Chenglong, Zhang, Jie, and Cheng, Xin, E-mail: kailiu@mail.ustc.edu.cn. Fri . "EXTREMELY LARGE EUV LATE PHASE OF SOLAR FLARES". United States. doi:10.1088/0004-637X/802/1/35.
@article{osti_22522033,
title = {EXTREMELY LARGE EUV LATE PHASE OF SOLAR FLARES},
author = {Liu, Kai and Wang, Yuming and Liu, Rui and Shen, Chenglong and Zhang, Jie and Cheng, Xin, E-mail: kailiu@mail.ustc.edu.cn},
abstractNote = {The second peak in the Fe xvi 33.5 nm line irradiance observed during solar flares by the Extreme-Ultraviolet Variability Experiment (EVE) is known as the EUV late phase. Our previous paper in 2013 by Liu et al. found that the main emissions in the late phase are originated from large-scale loop arcades that are closely connected to but different from the post-flare loops (PFLs), and we also proposed that a long cooling process without additional heating could explain the late phase. In this paper, we define the extremely large late phase because it not only has a bigger peak in the warm 33.5 irradiance profile, but also releases more EUV radiative energy than the main phase. Through detailed inspection of the EUV images from three points of view, it was discovered that aside from the later-phase loop arcades, the main contributor of the extremely large late phase is a hot structure that fails to erupt. This hot structure is identified as a flux rope, which is quickly energized by the flare reconnection and later on continuously produces the thermal energy during the gradual phase. Together with the late-phase loop arcades, the flux rope failing to erupt with the additional heating create the extremely large EUV late phase.},
doi = {10.1088/0004-637X/802/1/35},
journal = {Astrophysical Journal},
number = 1,
volume = 802,
place = {United States},
year = {Fri Mar 20 00:00:00 EDT 2015},
month = {Fri Mar 20 00:00:00 EDT 2015}
}