Broadening of the differential emission measure by multi-shelled and turbulent loops

Tom Van Doorsselaere; Patrick Antolin; Kostas Karampelas

doi:10.1051/0004-6361/201834086

Broadening of the differential emission measure by multi-shelled and turbulent loops

Tom Van Doorsselaere, Patrick Antolin, Kostas Karampelas

Applied Mathematics

Research output: Contribution to journal › Article › peer-review

Abstract

Context. Broad differential emission measure (DEM) distributions in the corona are a sign of multi-thermal plasma along the line-of-sight.Traditionally, this is interpreted as evidence of multi-stranded loops. Recently, however, it has been shown that multi-stranded loops are unlikely to exist in the solar corona, because of their instability to transverse perturbations.

Aims. We aim to test if loop models subject to the Transverse Wave-Induced Kelvin-Helmholtz (TWIKH) instability result in broad DEMs, potentially explaining the observations. We took simulation snapshots and compute the numerical DEM. Moreover, we performed forward-modelling in the relevant AIA channels before reconstructing the DEM.

Results. We find that turbulent loop models broaden their initial DEM, because of the turbulent mixing. The width of the DEM is determined by the initial temperature contrast with the exterior.

Conclusions. We conclude that impulsively excited loop models have a rather narrow DEM, but that continuously driven models result in broad DEMs that are comparable to the observations.

Original language	English
Article number	A65
Number of pages	7
Journal	Astronomy & Astrophysics
Volume	620
Early online date	29 Nov 2018
DOIs	https://doi.org/10.1051/0004-6361/201834086
Publication status	Published - Dec 2018

Keywords

Magnetohydrodynamics
Sun: corona
Sun: oscillations
Turbulence
Instabilities

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10.1051/0004-6361/201834086

Doorsselaere-2018-Broadening-DEM-A&A-AAM
© 2018, ESO. This work has been made available online in accordance with the publisher’s policies. This is the author created accepted version manuscript following peer review and as such may differ slightly from the final published version. The final published version of this work is available at https://www.aanda.org/
Accepted author manuscript, 3.71 MB

http://adsabs.harvard.edu/abs/2018arXiv181006300V

The Cool Alter-Ego of the Hot: The Cool Alter-ego of the Hot Solar Corona
Antolin, P. (PI)
1/06/18 → 31/05/23
Project: Fellowship
H2020 ERC Consolidator - CORONALDOLLS: CORONALDOLLS
De Moortel, I. (PI)
European Research Council
1/10/15 → 30/09/20
Project: Standard
Plasma Theory: Solar and Magnetospheric Plasma Theory
Hood, A. W. (PI), Mackay, D. H. (CoI), Neukirch, T. (CoI), Parnell, C. E. (CoI), Priest, E. (CoI), Archontis, V. (Researcher), Cargill, P. (Researcher), De Moortel, I. (Researcher) & Wright, A. N. (Researcher)
Science & Technology Facilities Council
1/04/13 → 31/03/16
Project: Standard

Cite this

@article{5c4484136e7d4ccea67cc3b27add3d9f,

title = "Broadening of the differential emission measure by multi-shelled and turbulent loops",

abstract = "Context. Broad differential emission measure (DEM) distributions in the corona are a sign of multi-thermal plasma along the line-of-sight.Traditionally, this is interpreted as evidence of multi-stranded loops. Recently, however, it has been shown that multi-stranded loops are unlikely to exist in the solar corona, because of their instability to transverse perturbations. Aims. We aim to test if loop models subject to the Transverse Wave-Induced Kelvin-Helmholtz (TWIKH) instability result in broad DEMs, potentially explaining the observations. We took simulation snapshots and compute the numerical DEM. Moreover, we performed forward-modelling in the relevant AIA channels before reconstructing the DEM. Results. We find that turbulent loop models broaden their initial DEM, because of the turbulent mixing. The width of the DEM is determined by the initial temperature contrast with the exterior. Conclusions. We conclude that impulsively excited loop models have a rather narrow DEM, but that continuously driven models result in broad DEMs that are comparable to the observations.",

keywords = "Magnetohydrodynamics, Sun: corona, Sun: oscillations, Turbulence, Instabilities",

author = "{Van Doorsselaere}, Tom and Patrick Antolin and Kostas Karampelas",

note = "Funding: UK Science and Technology Facilities Council (Consolidated Grant ST/K000950/1), the European Union Horizon 2020 research and innovation programme (grant agreement No. 647214) and STFC Ernest Rutherford Fellowship (grant agreement No. ST/R004285/1) (PA).",

year = "2018",

month = dec,

doi = "10.1051/0004-6361/201834086",

language = "English",

volume = "620",

journal = "Astronomy & Astrophysics",

issn = "0004-6361",

publisher = "EDP SCIENCES S A",

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TY - JOUR

T1 - Broadening of the differential emission measure by multi-shelled and turbulent loops

AU - Van Doorsselaere, Tom

AU - Antolin, Patrick

AU - Karampelas, Kostas

N1 - Funding: UK Science and Technology Facilities Council (Consolidated Grant ST/K000950/1), the European Union Horizon 2020 research and innovation programme (grant agreement No. 647214) and STFC Ernest Rutherford Fellowship (grant agreement No. ST/R004285/1) (PA).

PY - 2018/12

Y1 - 2018/12

N2 - Context. Broad differential emission measure (DEM) distributions in the corona are a sign of multi-thermal plasma along the line-of-sight.Traditionally, this is interpreted as evidence of multi-stranded loops. Recently, however, it has been shown that multi-stranded loops are unlikely to exist in the solar corona, because of their instability to transverse perturbations. Aims. We aim to test if loop models subject to the Transverse Wave-Induced Kelvin-Helmholtz (TWIKH) instability result in broad DEMs, potentially explaining the observations. We took simulation snapshots and compute the numerical DEM. Moreover, we performed forward-modelling in the relevant AIA channels before reconstructing the DEM. Results. We find that turbulent loop models broaden their initial DEM, because of the turbulent mixing. The width of the DEM is determined by the initial temperature contrast with the exterior. Conclusions. We conclude that impulsively excited loop models have a rather narrow DEM, but that continuously driven models result in broad DEMs that are comparable to the observations.

AB - Context. Broad differential emission measure (DEM) distributions in the corona are a sign of multi-thermal plasma along the line-of-sight.Traditionally, this is interpreted as evidence of multi-stranded loops. Recently, however, it has been shown that multi-stranded loops are unlikely to exist in the solar corona, because of their instability to transverse perturbations. Aims. We aim to test if loop models subject to the Transverse Wave-Induced Kelvin-Helmholtz (TWIKH) instability result in broad DEMs, potentially explaining the observations. We took simulation snapshots and compute the numerical DEM. Moreover, we performed forward-modelling in the relevant AIA channels before reconstructing the DEM. Results. We find that turbulent loop models broaden their initial DEM, because of the turbulent mixing. The width of the DEM is determined by the initial temperature contrast with the exterior. Conclusions. We conclude that impulsively excited loop models have a rather narrow DEM, but that continuously driven models result in broad DEMs that are comparable to the observations.

KW - Magnetohydrodynamics

KW - Sun: corona

KW - Sun: oscillations

KW - Turbulence

KW - Instabilities

U2 - 10.1051/0004-6361/201834086

DO - 10.1051/0004-6361/201834086

M3 - Article

SN - 0004-6361

VL - 620

JO - Astronomy & Astrophysics

JF - Astronomy & Astrophysics

M1 - A65

ER -

Broadening of the differential emission measure by multi-shelled and turbulent loops

Abstract

Keywords

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Projects

The Cool Alter-Ego of the Hot: The Cool Alter-ego of the Hot Solar Corona

H2020 ERC Consolidator - CORONALDOLLS: CORONALDOLLS

Plasma Theory: Solar and Magnetospheric Plasma Theory

Cite this