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Title: Solar Coronal Loops Associated with Small-scale Mixed Polarity Surface Magnetic Fields

Abstract

How and where are coronal loops rooted in the solar lower atmosphere? The details of the magnetic environment and its evolution at the footpoints of coronal loops are crucial to understanding the processes of mass and energy supply to the solar corona. To address the above question, we use high-resolution line-of-sight magnetic field data from the Imaging Magnetograph eXperiment instrument on the Sunrise balloon-borne observatory and coronal observations from the Atmospheric Imaging Assembly onboard the Solar Dynamics Observatory of an emerging active region. We find that the coronal loops are often rooted at the locations with minor small-scale but persistent opposite-polarity magnetic elements very close to the larger dominant polarity. These opposite-polarity small-scale elements continually interact with the dominant polarity underlying the coronal loop through flux cancellation. At these locations we detect small inverse Y-shaped jets in chromospheric Ca ii H images obtained from the Sunrise Filter Imager during the flux cancellation. Our results indicate that magnetic flux cancellation and reconnection at the base of coronal loops due to mixed polarity fields might be a crucial feature for the supply of mass and energy into the corona.

Authors:
; ; ; ; ; ; ; ;  [1];  [2]; ;  [3];  [4];  [5];  [6]
  1. Max-Planck-Institut für Sonnensystemforschung, Justus-von-Liebig-Weg 3, D-37077 Göttingen (Germany)
  2. Grupo de Astronomía y Ciencias del Espacio, Universidad de Valencia, E-46980 Paterna, Valencia (Spain)
  3. Instituto de Astrofísica de Andalucía (CSIC), Apartado de Correos 3004, E-18080 Granada (Spain)
  4. Kiepenheuer-Institut für Sonnenphysik, Schöneckstr. 6, D-79104 Freiburg (Germany)
  5. National Solar Observatory, 3665 Discovery Drive, Boulder, CO 80303 (United States)
  6. High Altitude Observatory, National Center for Atmospheric Research, P.O. Box 3000, Boulder, CO 80307-3000 (United States)
Publication Date:
OSTI Identifier:
22661234
Resource Type:
Journal Article
Resource Relation:
Journal Name: Astrophysical Journal, Supplement Series; Journal Volume: 229; 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; AVAILABILITY; BALLOONS; CANCELLATION; FILTERS; IMAGES; JETS; MAGNETIC FIELDS; MAGNETIC FLUX; MASS; PHOTOSPHERE; RESOLUTION; SOLAR CORONA; SUN; SURFACES

Citation Formats

Chitta, L. P., Peter, H., Solanki, S. K., Barthol, P., Gandorfer, A., Gizon, L., Hirzberger, J., Riethmüller, T. L., Noort, M. van, Rodríguez, J. Blanco, Iniesta, J. C. Del Toro, Suárez, D. Orozco, Schmidt, W., Pillet, V. Martínez, and Knölker, M., E-mail: chitta@mps.mpg.de. Solar Coronal Loops Associated with Small-scale Mixed Polarity Surface Magnetic Fields. United States: N. p., 2017. Web. doi:10.3847/1538-4365/229/1/4.
Chitta, L. P., Peter, H., Solanki, S. K., Barthol, P., Gandorfer, A., Gizon, L., Hirzberger, J., Riethmüller, T. L., Noort, M. van, Rodríguez, J. Blanco, Iniesta, J. C. Del Toro, Suárez, D. Orozco, Schmidt, W., Pillet, V. Martínez, & Knölker, M., E-mail: chitta@mps.mpg.de. Solar Coronal Loops Associated with Small-scale Mixed Polarity Surface Magnetic Fields. United States. doi:10.3847/1538-4365/229/1/4.
Chitta, L. P., Peter, H., Solanki, S. K., Barthol, P., Gandorfer, A., Gizon, L., Hirzberger, J., Riethmüller, T. L., Noort, M. van, Rodríguez, J. Blanco, Iniesta, J. C. Del Toro, Suárez, D. Orozco, Schmidt, W., Pillet, V. Martínez, and Knölker, M., E-mail: chitta@mps.mpg.de. Wed . "Solar Coronal Loops Associated with Small-scale Mixed Polarity Surface Magnetic Fields". United States. doi:10.3847/1538-4365/229/1/4.
@article{osti_22661234,
title = {Solar Coronal Loops Associated with Small-scale Mixed Polarity Surface Magnetic Fields},
author = {Chitta, L. P. and Peter, H. and Solanki, S. K. and Barthol, P. and Gandorfer, A. and Gizon, L. and Hirzberger, J. and Riethmüller, T. L. and Noort, M. van and Rodríguez, J. Blanco and Iniesta, J. C. Del Toro and Suárez, D. Orozco and Schmidt, W. and Pillet, V. Martínez and Knölker, M., E-mail: chitta@mps.mpg.de},
abstractNote = {How and where are coronal loops rooted in the solar lower atmosphere? The details of the magnetic environment and its evolution at the footpoints of coronal loops are crucial to understanding the processes of mass and energy supply to the solar corona. To address the above question, we use high-resolution line-of-sight magnetic field data from the Imaging Magnetograph eXperiment instrument on the Sunrise balloon-borne observatory and coronal observations from the Atmospheric Imaging Assembly onboard the Solar Dynamics Observatory of an emerging active region. We find that the coronal loops are often rooted at the locations with minor small-scale but persistent opposite-polarity magnetic elements very close to the larger dominant polarity. These opposite-polarity small-scale elements continually interact with the dominant polarity underlying the coronal loop through flux cancellation. At these locations we detect small inverse Y-shaped jets in chromospheric Ca ii H images obtained from the Sunrise Filter Imager during the flux cancellation. Our results indicate that magnetic flux cancellation and reconnection at the base of coronal loops due to mixed polarity fields might be a crucial feature for the supply of mass and energy into the corona.},
doi = {10.3847/1538-4365/229/1/4},
journal = {Astrophysical Journal, Supplement Series},
number = 1,
volume = 229,
place = {United States},
year = {Wed Mar 01 00:00:00 EST 2017},
month = {Wed Mar 01 00:00:00 EST 2017}
}
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