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Title: ON THE ORIGIN OF THE TYPE II SPICULES: DYNAMIC THREE-DIMENSIONAL MHD SIMULATIONS

Abstract

Recent high temporal and spatial resolution observations of the chromosphere have forced the definition of a new type of spicule, 'type II's', that are characterized by rising rapidly, having short lives, and by fading away at the end of their lifetimes. Here, we report on features found in realistic three-dimensional simulations of the outer solar atmosphere that resemble the observed type II spicules. These features evolve naturally from the simulations as a consequence of the magnetohydrodynamical evolution of the model atmosphere. The simulations span from the upper layer of the convection zone to the lower corona and include the emergence of a horizontal magnetic flux. The state-of-art Oslo Staggered Code is used to solve the full MHD equations with non-gray and non-LTE radiative transfer and thermal conduction along the magnetic field lines. We describe in detail the physics involved in a process which we consider a possible candidate for the driver mechanism that produces type II spicules. The modeled spicule is composed of material rapidly ejected from the chromosphere that rises into the corona while being heated. Its source lies in a region with large field gradients and intense electric currents, which lead to a strong Lorentz force that squeezesmore » the chromospheric material, resulting in a vertical pressure gradient that propels the spicule along the magnetic field, as well as Joule heating, which heats the jet material, forcing it to fade.« less

Authors:
 [1];  [2];  [3]
  1. Lockheed Martin Solar and Astrophysics Laboratory, Palo Alto, CA 94304 (United States)
  2. Institute of Theoretical Astrophysics, University of Oslo, P.O. Box 1029 Blindern, N-0315 Oslo (Norway)
  3. Instituto de Astrofisica de Canarias, 38200 La Laguna (Tenerife) (Spain)
Publication Date:
OSTI Identifier:
21578363
Resource Type:
Journal Article
Journal Name:
Astrophysical Journal
Additional Journal Information:
Journal Volume: 736; Journal Issue: 1; Other Information: DOI: 10.1088/0004-637X/736/1/9; Journal ID: ISSN 0004-637X
Country of Publication:
United States
Language:
English
Subject:
79 ASTROPHYSICS, COSMOLOGY AND ASTRONOMY; CHROMOSPHERE; CONVECTION; LTE; MAGNETIC FLUX; MAGNETOHYDRODYNAMICS; RADIANT HEAT TRANSFER; SIMULATION; SOLAR CORONA; SOLAR PROMINENCES; THREE-DIMENSIONAL CALCULATIONS; ATMOSPHERES; ENERGY TRANSFER; EQUILIBRIUM; FLUID MECHANICS; HEAT TRANSFER; HYDRODYNAMICS; MASS TRANSFER; MECHANICS; SOLAR ACTIVITY; SOLAR ATMOSPHERE; STELLAR ACTIVITY; STELLAR ATMOSPHERES; STELLAR CORONAE

Citation Formats

MartInez-Sykora, Juan, Hansteen, Viggo, and Moreno-Insertis, Fernando. ON THE ORIGIN OF THE TYPE II SPICULES: DYNAMIC THREE-DIMENSIONAL MHD SIMULATIONS. United States: N. p., 2011. Web. doi:10.1088/0004-637X/736/1/9.
MartInez-Sykora, Juan, Hansteen, Viggo, & Moreno-Insertis, Fernando. ON THE ORIGIN OF THE TYPE II SPICULES: DYNAMIC THREE-DIMENSIONAL MHD SIMULATIONS. United States. https://doi.org/10.1088/0004-637X/736/1/9
MartInez-Sykora, Juan, Hansteen, Viggo, and Moreno-Insertis, Fernando. 2011. "ON THE ORIGIN OF THE TYPE II SPICULES: DYNAMIC THREE-DIMENSIONAL MHD SIMULATIONS". United States. https://doi.org/10.1088/0004-637X/736/1/9.
@article{osti_21578363,
title = {ON THE ORIGIN OF THE TYPE II SPICULES: DYNAMIC THREE-DIMENSIONAL MHD SIMULATIONS},
author = {MartInez-Sykora, Juan and Hansteen, Viggo and Moreno-Insertis, Fernando},
abstractNote = {Recent high temporal and spatial resolution observations of the chromosphere have forced the definition of a new type of spicule, 'type II's', that are characterized by rising rapidly, having short lives, and by fading away at the end of their lifetimes. Here, we report on features found in realistic three-dimensional simulations of the outer solar atmosphere that resemble the observed type II spicules. These features evolve naturally from the simulations as a consequence of the magnetohydrodynamical evolution of the model atmosphere. The simulations span from the upper layer of the convection zone to the lower corona and include the emergence of a horizontal magnetic flux. The state-of-art Oslo Staggered Code is used to solve the full MHD equations with non-gray and non-LTE radiative transfer and thermal conduction along the magnetic field lines. We describe in detail the physics involved in a process which we consider a possible candidate for the driver mechanism that produces type II spicules. The modeled spicule is composed of material rapidly ejected from the chromosphere that rises into the corona while being heated. Its source lies in a region with large field gradients and intense electric currents, which lead to a strong Lorentz force that squeezes the chromospheric material, resulting in a vertical pressure gradient that propels the spicule along the magnetic field, as well as Joule heating, which heats the jet material, forcing it to fade.},
doi = {10.1088/0004-637X/736/1/9},
url = {https://www.osti.gov/biblio/21578363}, journal = {Astrophysical Journal},
issn = {0004-637X},
number = 1,
volume = 736,
place = {United States},
year = {Wed Jul 20 00:00:00 EDT 2011},
month = {Wed Jul 20 00:00:00 EDT 2011}
}