Numerical simulation of the three-dimensional structure and dynamics of the non-magnetic solar chromosphere
(2004) In Astronomy & Astrophysics 414(3). p.1121-1137- Abstract
- Three-dimensional numerical simulations with CO<SUP>5</SUP>, a newradiation hydrodynamics code, result in a dynamic, thermally bifurcatedmodel of the non-magnetic chromosphere of the quiet Sun. The 3D modelincludes the middle and low chromosphere, the photosphere, and the topof the convection zone, where acoustic waves are excited by convectivemotions. While the waves propagate upwards, they steepen into shocks,dissipate, and deposit their mechanienergy as heat in the chromosphere.Our numerical simulations show for the first time a complex 3D structureof the chromospheric layers, formed by the interaction of shock waves.Horizontal temperature cross-sections of the model chromosphere exhibita network of hot filaments and... (More)
- Three-dimensional numerical simulations with CO<SUP>5</SUP>, a newradiation hydrodynamics code, result in a dynamic, thermally bifurcatedmodel of the non-magnetic chromosphere of the quiet Sun. The 3D modelincludes the middle and low chromosphere, the photosphere, and the topof the convection zone, where acoustic waves are excited by convectivemotions. While the waves propagate upwards, they steepen into shocks,dissipate, and deposit their mechanienergy as heat in the chromosphere.Our numerical simulations show for the first time a complex 3D structureof the chromospheric layers, formed by the interaction of shock waves.Horizontal temperature cross-sections of the model chromosphere exhibita network of hot filaments and enclosed cool regions. The horizontalpattern evolves on short time-scales of the order of typically 20-25 s,and has spatial scales comparable to those of the underlyinggranulation. The resulting thermal bifurcation, i.e., the co-existenceof cold and hot regions, provides temperatures high enough to producethe observed chromospheric UV emission and - at the same time -temperatures cold enough to allow the formation of molecules (e.g.,carbon monoxide). Our 3D model corroborates the finding bycitet{carlsson94} that the chromospheric temperature rise ofsemi-empirical models does not necessarily imply an increase in theaverage gas temperature but can be explained by the presence ofsubstantial spatial and temporal temperature inhomogeneities. (Less)
Please use this url to cite or link to this publication:
https://lup.lub.lu.se/record/129638
- author
- Wedemeyer, S. ; Freytag, B. ; Steffen, M. ; Ludwig, Hans-Günter LU and Holweger, H.
- organization
- publishing date
- 2004
- type
- Contribution to journal
- publication status
- published
- subject
- keywords
- Sun: chromosphere, hydrodynamics, radiative transfer
- in
- Astronomy & Astrophysics
- volume
- 414
- issue
- 3
- pages
- 1121 - 1137
- publisher
- EDP Sciences
- external identifiers
-
- wos:000189377200036
- scopus:1042300861
- ISSN
- 0004-6361
- DOI
- 10.1051/0004-6361:20031682
- language
- English
- LU publication?
- yes
- id
- e5a4c01c-f597-4cbd-b718-99321ee301c5 (old id 129638)
- date added to LUP
- 2016-04-01 17:03:56
- date last changed
- 2024-02-10 14:45:45
@article{e5a4c01c-f597-4cbd-b718-99321ee301c5,
abstract = {{Three-dimensional numerical simulations with CO<SUP>5</SUP>, a newradiation hydrodynamics code, result in a dynamic, thermally bifurcatedmodel of the non-magnetic chromosphere of the quiet Sun. The 3D modelincludes the middle and low chromosphere, the photosphere, and the topof the convection zone, where acoustic waves are excited by convectivemotions. While the waves propagate upwards, they steepen into shocks,dissipate, and deposit their mechanienergy as heat in the chromosphere.Our numerical simulations show for the first time a complex 3D structureof the chromospheric layers, formed by the interaction of shock waves.Horizontal temperature cross-sections of the model chromosphere exhibita network of hot filaments and enclosed cool regions. The horizontalpattern evolves on short time-scales of the order of typically 20-25 s,and has spatial scales comparable to those of the underlyinggranulation. The resulting thermal bifurcation, i.e., the co-existenceof cold and hot regions, provides temperatures high enough to producethe observed chromospheric UV emission and - at the same time -temperatures cold enough to allow the formation of molecules (e.g.,carbon monoxide). Our 3D model corroborates the finding bycitet{carlsson94} that the chromospheric temperature rise ofsemi-empirical models does not necessarily imply an increase in theaverage gas temperature but can be explained by the presence ofsubstantial spatial and temporal temperature inhomogeneities.}},
author = {{Wedemeyer, S. and Freytag, B. and Steffen, M. and Ludwig, Hans-Günter and Holweger, H.}},
issn = {{0004-6361}},
keywords = {{Sun: chromosphere; hydrodynamics; radiative transfer}},
language = {{eng}},
number = {{3}},
pages = {{1121--1137}},
publisher = {{EDP Sciences}},
series = {{Astronomy & Astrophysics}},
title = {{Numerical simulation of the three-dimensional structure and dynamics of the non-magnetic solar chromosphere}},
url = {{https://lup.lub.lu.se/search/files/4863736/624109.pdf}},
doi = {{10.1051/0004-6361:20031682}},
volume = {{414}},
year = {{2004}},
}