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Title: ISOTHERMAL AND MULTITHERMAL ANALYSIS OF CORONAL LOOPS OBSERVED WITH ATMOSPHERIC IMAGING ASSEMBLY. II. 211 A SELECTED LOOPS

Abstract

An important component of coronal loop analysis involves conflicting results on the cross-field temperature distribution. Are loops isothermal or multithermal? The Atmospheric Imaging Assembly (AIA) on board the Solar Dynamics Observatory was designed in part to answer this question. AIA has a series of coronal filters that peak at different temperatures and cover the entire active region temperature range. These properties should make AIA ideal for multithermal analysis, but recent results have shown that the response functions of two of the filters, AIA 94 and 131 A, are missing a significant number of low-temperature emission lines. Here we analyze coronal loops from several active regions that were chosen in the 211 A channel of AIA, which has a peak response temperature of log T = 6.3. The differential emission measure (DEM) analysis of the 12 loops in our sample reveals that using data from the 131 A AIA filter distorts the results, and we have no choice but to do the analysis without these data. The 94 A data do not appear to be as important, simply because the chosen loops are not visible in this channel. If we eliminate the 131 A data, however, we find that our DEMmore » analysis is not well constrained on the cool temperature end of six of our loops. The information revealed by our 211 selected loops indicates that additional atomic data are required in order to pin down the cross-field temperature distribution.« less

Authors:
; ; ; ; ;  [1];  [2]
  1. Physics Department, University of Memphis, Memphis, TN 38152 (United States)
  2. Harvard-Smithsonian Center for Astrophysics, Cambridge, MA 02138 (United States)
Publication Date:
OSTI Identifier:
21587519
Resource Type:
Journal Article
Journal Name:
Astrophysical Journal
Additional Journal Information:
Journal Volume: 739; Journal Issue: 1; Other Information: DOI: 10.1088/0004-637X/739/1/33; Country of input: International Atomic Energy Agency (IAEA); Journal ID: ISSN 0004-637X
Country of Publication:
United States
Language:
English
Subject:
79 ASTROPHYSICS, COSMOLOGY AND ASTRONOMY; EMISSION; SOLAR CORONA; TEMPERATURE DISTRIBUTION; ATMOSPHERES; SOLAR ATMOSPHERE; STELLAR ATMOSPHERES; STELLAR CORONAE

Citation Formats

Schmelz, J. T., Worley, B. T., Anderson, D. J., Pathak, S., Kimble, J. A., Jenkins, B. S., and Saar, S. H., E-mail: jschmelz@memphis.edu. ISOTHERMAL AND MULTITHERMAL ANALYSIS OF CORONAL LOOPS OBSERVED WITH ATMOSPHERIC IMAGING ASSEMBLY. II. 211 A SELECTED LOOPS. United States: N. p., 2011. Web. doi:10.1088/0004-637X/739/1/33; COUNTRY OF INPUT: INTERNATIONAL ATOMIC ENERGY AGENCY (IAEA).
Schmelz, J. T., Worley, B. T., Anderson, D. J., Pathak, S., Kimble, J. A., Jenkins, B. S., & Saar, S. H., E-mail: jschmelz@memphis.edu. ISOTHERMAL AND MULTITHERMAL ANALYSIS OF CORONAL LOOPS OBSERVED WITH ATMOSPHERIC IMAGING ASSEMBLY. II. 211 A SELECTED LOOPS. United States. doi:10.1088/0004-637X/739/1/33; COUNTRY OF INPUT: INTERNATIONAL ATOMIC ENERGY AGENCY (IAEA).
Schmelz, J. T., Worley, B. T., Anderson, D. J., Pathak, S., Kimble, J. A., Jenkins, B. S., and Saar, S. H., E-mail: jschmelz@memphis.edu. Tue . "ISOTHERMAL AND MULTITHERMAL ANALYSIS OF CORONAL LOOPS OBSERVED WITH ATMOSPHERIC IMAGING ASSEMBLY. II. 211 A SELECTED LOOPS". United States. doi:10.1088/0004-637X/739/1/33; COUNTRY OF INPUT: INTERNATIONAL ATOMIC ENERGY AGENCY (IAEA).
@article{osti_21587519,
title = {ISOTHERMAL AND MULTITHERMAL ANALYSIS OF CORONAL LOOPS OBSERVED WITH ATMOSPHERIC IMAGING ASSEMBLY. II. 211 A SELECTED LOOPS},
author = {Schmelz, J. T. and Worley, B. T. and Anderson, D. J. and Pathak, S. and Kimble, J. A. and Jenkins, B. S. and Saar, S. H., E-mail: jschmelz@memphis.edu},
abstractNote = {An important component of coronal loop analysis involves conflicting results on the cross-field temperature distribution. Are loops isothermal or multithermal? The Atmospheric Imaging Assembly (AIA) on board the Solar Dynamics Observatory was designed in part to answer this question. AIA has a series of coronal filters that peak at different temperatures and cover the entire active region temperature range. These properties should make AIA ideal for multithermal analysis, but recent results have shown that the response functions of two of the filters, AIA 94 and 131 A, are missing a significant number of low-temperature emission lines. Here we analyze coronal loops from several active regions that were chosen in the 211 A channel of AIA, which has a peak response temperature of log T = 6.3. The differential emission measure (DEM) analysis of the 12 loops in our sample reveals that using data from the 131 A AIA filter distorts the results, and we have no choice but to do the analysis without these data. The 94 A data do not appear to be as important, simply because the chosen loops are not visible in this channel. If we eliminate the 131 A data, however, we find that our DEM analysis is not well constrained on the cool temperature end of six of our loops. The information revealed by our 211 selected loops indicates that additional atomic data are required in order to pin down the cross-field temperature distribution.},
doi = {10.1088/0004-637X/739/1/33; COUNTRY OF INPUT: INTERNATIONAL ATOMIC ENERGY AGENCY (IAEA)},
journal = {Astrophysical Journal},
issn = {0004-637X},
number = 1,
volume = 739,
place = {United States},
year = {2011},
month = {9}
}