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Title: Observational Signatures of a Kink-unstable Coronal Flux Rope Using Hinode /EIS

Abstract

The signatures of energy release and energy transport for a kink-unstable coronal flux rope are investigated via forward modeling. Synthetic intensity and Doppler maps are generated from a 3D numerical simulation. The CHIANTI database is used to compute intensities for three Hinode /EIS emission lines that cover the thermal range of the loop. The intensities and Doppler velocities at simulation-resolution are spatially degraded to the Hinode /EIS pixel size (1″), convolved using a Gaussian point-spread function (3″), and exposed for a characteristic time of 50 s. The synthetic images generated for rasters (moving slit) and sit-and-stare (stationary slit) are analyzed to find the signatures of the twisted flux and the associated instability. We find that there are several qualities of a kink-unstable coronal flux rope that can be detected observationally using Hinode /EIS, namely the growth of the loop radius, the increase in intensity toward the radial edge of the loop, and the Doppler velocity following an internal twisted magnetic field line. However, EIS cannot resolve the small, transient features present in the simulation, such as sites of small-scale reconnection (e.g., nanoflares).

Authors:
; ; ; ;  [1];  [2]
  1. Northumbria University, Newcastle upon Tyne, NE1 8ST (United Kingdom)
  2. University of Warwick, Coventry, CV4 7AL (United Kingdom)
Publication Date:
OSTI Identifier:
22663525
Resource Type:
Journal Article
Resource Relation:
Journal Name: Astrophysical Journal; Journal Volume: 842; 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; COMPUTERIZED SIMULATION; EMISSION; INSTABILITY; MAGNETIC FIELDS; MAGNETIC RECONNECTION; MAGNETOHYDRODYNAMICS; RESOLUTION; SUN; THREE-DIMENSIONAL CALCULATIONS; ULTRAVIOLET RADIATION; VELOCITY

Citation Formats

Snow, B., Botha, G. J. J., Régnier, S., Morton, R. J., Young, P. R., and Verwichte, E.. Observational Signatures of a Kink-unstable Coronal Flux Rope Using Hinode /EIS. United States: N. p., 2017. Web. doi:10.3847/1538-4357/AA6D0E.
Snow, B., Botha, G. J. J., Régnier, S., Morton, R. J., Young, P. R., & Verwichte, E.. Observational Signatures of a Kink-unstable Coronal Flux Rope Using Hinode /EIS. United States. doi:10.3847/1538-4357/AA6D0E.
Snow, B., Botha, G. J. J., Régnier, S., Morton, R. J., Young, P. R., and Verwichte, E.. Sat . "Observational Signatures of a Kink-unstable Coronal Flux Rope Using Hinode /EIS". United States. doi:10.3847/1538-4357/AA6D0E.
@article{osti_22663525,
title = {Observational Signatures of a Kink-unstable Coronal Flux Rope Using Hinode /EIS},
author = {Snow, B. and Botha, G. J. J. and Régnier, S. and Morton, R. J. and Young, P. R. and Verwichte, E.},
abstractNote = {The signatures of energy release and energy transport for a kink-unstable coronal flux rope are investigated via forward modeling. Synthetic intensity and Doppler maps are generated from a 3D numerical simulation. The CHIANTI database is used to compute intensities for three Hinode /EIS emission lines that cover the thermal range of the loop. The intensities and Doppler velocities at simulation-resolution are spatially degraded to the Hinode /EIS pixel size (1″), convolved using a Gaussian point-spread function (3″), and exposed for a characteristic time of 50 s. The synthetic images generated for rasters (moving slit) and sit-and-stare (stationary slit) are analyzed to find the signatures of the twisted flux and the associated instability. We find that there are several qualities of a kink-unstable coronal flux rope that can be detected observationally using Hinode /EIS, namely the growth of the loop radius, the increase in intensity toward the radial edge of the loop, and the Doppler velocity following an internal twisted magnetic field line. However, EIS cannot resolve the small, transient features present in the simulation, such as sites of small-scale reconnection (e.g., nanoflares).},
doi = {10.3847/1538-4357/AA6D0E},
journal = {Astrophysical Journal},
number = 1,
volume = 842,
place = {United States},
year = {Sat Jun 10 00:00:00 EDT 2017},
month = {Sat Jun 10 00:00:00 EDT 2017}
}
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