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Title: Are All Flare Ribbons Simply Connected to the Corona?

Abstract

We consider the observational basis for the belief that flare ribbons in the chromosphere result from energy transport from the overlying corona. We study ribbons of small flares using magnetic and intensity data from the Hinode , Solar Dynamics Observatory , and IRIS missions. While most ribbons appear connected to the corona and overlie regions of significant vertical magnetic field, we examine one ribbon with no clear evidence for such connections. Evolving horizontal magnetic fields seen with Hinode suggest that reconnection with preexisting fields below the corona can explain the data. The identification of just one, albeit small, ribbon, with no apparent connection to the corona, leads us to conclude that at least two mechanisms are responsible for the heating that leads to flare ribbon emission.

Authors:
 [1]; ; ;  [2];  [3]
  1. High Altitude Observatory, National Center for Atmospheric Research, P.O. Box 3000, Boulder, CO 80307-3000 (United States)
  2. Monash Center for Astrophysics, School of Mathematical Science, Monash University, Victoria 3800 (Australia)
  3. Northwest Research Associates, 3380 Mitchell Lane, Boulder, CO 80301 (United States)
Publication Date:
OSTI Identifier:
22661190
Resource Type:
Journal Article
Resource Relation:
Journal Name: Astrophysical Journal; Journal Volume: 838; 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; CHROMOSPHERE; EMISSION; MAGNETIC FIELDS; POWER TRANSMISSION; SOLAR CORONA; SOLAR FLARES; SUN; ULTRAVIOLET RADIATION

Citation Formats

Judge, Philip G., Paraschiv, Alin, Lacatus, Daniela, Donea, Alina, and Lindsey, Charlie, E-mail: judge@ucar.edu, E-mail: alina.donea@monash.edu, E-mail: alin.paraschiv@monash.edu, E-mail: daniela.lacatus@monash.edu, E-mail: indsey@cora.nwra.com. Are All Flare Ribbons Simply Connected to the Corona?. United States: N. p., 2017. Web. doi:10.3847/1538-4357/AA656C.
Judge, Philip G., Paraschiv, Alin, Lacatus, Daniela, Donea, Alina, & Lindsey, Charlie, E-mail: judge@ucar.edu, E-mail: alina.donea@monash.edu, E-mail: alin.paraschiv@monash.edu, E-mail: daniela.lacatus@monash.edu, E-mail: indsey@cora.nwra.com. Are All Flare Ribbons Simply Connected to the Corona?. United States. doi:10.3847/1538-4357/AA656C.
Judge, Philip G., Paraschiv, Alin, Lacatus, Daniela, Donea, Alina, and Lindsey, Charlie, E-mail: judge@ucar.edu, E-mail: alina.donea@monash.edu, E-mail: alin.paraschiv@monash.edu, E-mail: daniela.lacatus@monash.edu, E-mail: indsey@cora.nwra.com. Sat . "Are All Flare Ribbons Simply Connected to the Corona?". United States. doi:10.3847/1538-4357/AA656C.
@article{osti_22661190,
title = {Are All Flare Ribbons Simply Connected to the Corona?},
author = {Judge, Philip G. and Paraschiv, Alin and Lacatus, Daniela and Donea, Alina and Lindsey, Charlie, E-mail: judge@ucar.edu, E-mail: alina.donea@monash.edu, E-mail: alin.paraschiv@monash.edu, E-mail: daniela.lacatus@monash.edu, E-mail: indsey@cora.nwra.com},
abstractNote = {We consider the observational basis for the belief that flare ribbons in the chromosphere result from energy transport from the overlying corona. We study ribbons of small flares using magnetic and intensity data from the Hinode , Solar Dynamics Observatory , and IRIS missions. While most ribbons appear connected to the corona and overlie regions of significant vertical magnetic field, we examine one ribbon with no clear evidence for such connections. Evolving horizontal magnetic fields seen with Hinode suggest that reconnection with preexisting fields below the corona can explain the data. The identification of just one, albeit small, ribbon, with no apparent connection to the corona, leads us to conclude that at least two mechanisms are responsible for the heating that leads to flare ribbon emission.},
doi = {10.3847/1538-4357/AA656C},
journal = {Astrophysical Journal},
number = 2,
volume = 838,
place = {United States},
year = {Sat Apr 01 00:00:00 EDT 2017},
month = {Sat Apr 01 00:00:00 EDT 2017}
}
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