Two-dimensional cellular automaton model for the evolution of active region coronal plasmas
We study a two-dimensional cellular automaton (CA) model for the evolution of coronal loop plasmas. The model is based on the idea that coronal loops are made of elementary magnetic strands that are tangled and stressed by the displacement of their footpoints by photospheric motions. The magnetic st...
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paper:paper_0004637X_v799_n2_p_Fuentes2023-06-08T14:29:13Z Two-dimensional cellular automaton model for the evolution of active region coronal plasmas Sun: Activity Sun: Corona Sun: Magnetic fields Sun: X-rays, gamma rays We study a two-dimensional cellular automaton (CA) model for the evolution of coronal loop plasmas. The model is based on the idea that coronal loops are made of elementary magnetic strands that are tangled and stressed by the displacement of their footpoints by photospheric motions. The magnetic stress accumulated between neighbor strands is released in sudden reconnection events or nanoflares that heat the plasma. We combine the CA model with the Enthalpy Based Thermal Evolution of Loops model to compute the response of the plasma to the heating events. Using the known response of the X-Ray Telescope on board Hinode, we also obtain synthetic data. The model obeys easy-to-understand scaling laws relating the output (nanoflare energy, temperature, density, intensity) to the input parameters (field strength, strand length, critical misalignment angle). The nanoflares have a powerlaw distribution with a universal slope of -2.5, independent of the input parameters. The repetition frequency of nanoflares, expressed in terms of the plasma cooling time, increases with strand length. We discuss the implications of our results for the problem of heating and evolution of active region coronal plasmas. © 2015. The American Astronomical Society. All rights reserved. 2015 https://bibliotecadigital.exactas.uba.ar/collection/paper/document/paper_0004637X_v799_n2_p_Fuentes http://hdl.handle.net/20.500.12110/paper_0004637X_v799_n2_p_Fuentes |
institution |
Universidad de Buenos Aires |
institution_str |
I-28 |
repository_str |
R-134 |
collection |
Biblioteca Digital - Facultad de Ciencias Exactas y Naturales (UBA) |
topic |
Sun: Activity Sun: Corona Sun: Magnetic fields Sun: X-rays, gamma rays |
spellingShingle |
Sun: Activity Sun: Corona Sun: Magnetic fields Sun: X-rays, gamma rays Two-dimensional cellular automaton model for the evolution of active region coronal plasmas |
topic_facet |
Sun: Activity Sun: Corona Sun: Magnetic fields Sun: X-rays, gamma rays |
description |
We study a two-dimensional cellular automaton (CA) model for the evolution of coronal loop plasmas. The model is based on the idea that coronal loops are made of elementary magnetic strands that are tangled and stressed by the displacement of their footpoints by photospheric motions. The magnetic stress accumulated between neighbor strands is released in sudden reconnection events or nanoflares that heat the plasma. We combine the CA model with the Enthalpy Based Thermal Evolution of Loops model to compute the response of the plasma to the heating events. Using the known response of the X-Ray Telescope on board Hinode, we also obtain synthetic data. The model obeys easy-to-understand scaling laws relating the output (nanoflare energy, temperature, density, intensity) to the input parameters (field strength, strand length, critical misalignment angle). The nanoflares have a powerlaw distribution with a universal slope of -2.5, independent of the input parameters. The repetition frequency of nanoflares, expressed in terms of the plasma cooling time, increases with strand length. We discuss the implications of our results for the problem of heating and evolution of active region coronal plasmas. © 2015. The American Astronomical Society. All rights reserved. |
title |
Two-dimensional cellular automaton model for the evolution of active region coronal plasmas |
title_short |
Two-dimensional cellular automaton model for the evolution of active region coronal plasmas |
title_full |
Two-dimensional cellular automaton model for the evolution of active region coronal plasmas |
title_fullStr |
Two-dimensional cellular automaton model for the evolution of active region coronal plasmas |
title_full_unstemmed |
Two-dimensional cellular automaton model for the evolution of active region coronal plasmas |
title_sort |
two-dimensional cellular automaton model for the evolution of active region coronal plasmas |
publishDate |
2015 |
url |
https://bibliotecadigital.exactas.uba.ar/collection/paper/document/paper_0004637X_v799_n2_p_Fuentes http://hdl.handle.net/20.500.12110/paper_0004637X_v799_n2_p_Fuentes |
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1768544436748288000 |