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Title: COMBINED STEREO/RHESSI STUDY OF CORONAL MASS EJECTION ACCELERATION AND PARTICLE ACCELERATION IN SOLAR FLARES

Abstract

Using the potential of two unprecedented missions, Solar Terrestrial Relations Observatory (STEREO) and Reuven Ramaty High-Energy Solar Spectroscopic Imager (RHESSI), we study three well-observed fast coronal mass ejections (CMEs) that occurred close to the limb together with their associated high-energy flare emissions in terms of RHESSI hard X-ray (HXR) spectra and flux evolution. From STEREO/EUVI and STEREO/COR1 data, the full CME kinematics of the impulsive acceleration phase up to {approx}4 R{sub sun} is measured with a high time cadence of <=2.5 minutes. For deriving CME velocity and acceleration, we apply and test a new algorithm based on regularization methods. The CME maximum acceleration is achieved at heights h <= 0.4 R{sub sun}, and the peak velocity at h <= 2.1 R{sub sun} (in one case, as small as 0.5 R{sub sun}). We find that the CME acceleration profile and the flare energy release as evidenced in the RHESSI HXR flux evolve in a synchronized manner. These results support the 'standard' flare/CME model which is characterized by a feedback relationship between the large-scale CME acceleration process and the energy release in the associated flare.

Authors:
;  [1];  [2];  [3];  [4]
  1. IGAM/Kanzelhoehe Observatory, Institute of Physics, Universitaet Graz, Universitaetsplatz 5, A-8010 Graz (Austria)
  2. Department of Physics and Astronomy, University of Glasgow, Glasgow G12 8QQ (United Kingdom)
  3. Space Sciences Laboratory, University of California, Berkeley, CA 94720-7450 (United States)
  4. Hvar Observatory, Faculty of Geodesy, University of Zagreb, Kaciceva 26, HR-10000 Zagreb (Croatia)
Publication Date:
OSTI Identifier:
21394174
Resource Type:
Journal Article
Resource Relation:
Journal Name: Astrophysical Journal; Journal Volume: 712; Journal Issue: 2; Other Information: DOI: 10.1088/0004-637X/712/2/1410
Country of Publication:
United States
Language:
English
Subject:
79 ASTROPHYSICS, COSMOLOGY AND ASTRONOMY; ACCELERATION; ALGORITHMS; EMISSION; GAMMA RADIATION; HARD X RADIATION; MASS; SOLAR FLARES; SUN; ELECTROMAGNETIC RADIATION; IONIZING RADIATIONS; MAIN SEQUENCE STARS; MATHEMATICAL LOGIC; RADIATIONS; SOLAR ACTIVITY; STARS; STELLAR ACTIVITY; STELLAR FLARES; X RADIATION

Citation Formats

Temmer, M., Veronig, A. M., Kontar, E. P., Krucker, S., and Vrsnak, B., E-mail: mat@igam.uni-graz.a, E-mail: asv@igam.uni-graz.a, E-mail: eduard@astro.gla.ac.u, E-mail: krucker@ssl.berkeley.ed, E-mail: bvrsnak@gmail.co. COMBINED STEREO/RHESSI STUDY OF CORONAL MASS EJECTION ACCELERATION AND PARTICLE ACCELERATION IN SOLAR FLARES. United States: N. p., 2010. Web. doi:10.1088/0004-637X/712/2/1410.
Temmer, M., Veronig, A. M., Kontar, E. P., Krucker, S., & Vrsnak, B., E-mail: mat@igam.uni-graz.a, E-mail: asv@igam.uni-graz.a, E-mail: eduard@astro.gla.ac.u, E-mail: krucker@ssl.berkeley.ed, E-mail: bvrsnak@gmail.co. COMBINED STEREO/RHESSI STUDY OF CORONAL MASS EJECTION ACCELERATION AND PARTICLE ACCELERATION IN SOLAR FLARES. United States. doi:10.1088/0004-637X/712/2/1410.
Temmer, M., Veronig, A. M., Kontar, E. P., Krucker, S., and Vrsnak, B., E-mail: mat@igam.uni-graz.a, E-mail: asv@igam.uni-graz.a, E-mail: eduard@astro.gla.ac.u, E-mail: krucker@ssl.berkeley.ed, E-mail: bvrsnak@gmail.co. Thu . "COMBINED STEREO/RHESSI STUDY OF CORONAL MASS EJECTION ACCELERATION AND PARTICLE ACCELERATION IN SOLAR FLARES". United States. doi:10.1088/0004-637X/712/2/1410.
@article{osti_21394174,
title = {COMBINED STEREO/RHESSI STUDY OF CORONAL MASS EJECTION ACCELERATION AND PARTICLE ACCELERATION IN SOLAR FLARES},
author = {Temmer, M. and Veronig, A. M. and Kontar, E. P. and Krucker, S. and Vrsnak, B., E-mail: mat@igam.uni-graz.a, E-mail: asv@igam.uni-graz.a, E-mail: eduard@astro.gla.ac.u, E-mail: krucker@ssl.berkeley.ed, E-mail: bvrsnak@gmail.co},
abstractNote = {Using the potential of two unprecedented missions, Solar Terrestrial Relations Observatory (STEREO) and Reuven Ramaty High-Energy Solar Spectroscopic Imager (RHESSI), we study three well-observed fast coronal mass ejections (CMEs) that occurred close to the limb together with their associated high-energy flare emissions in terms of RHESSI hard X-ray (HXR) spectra and flux evolution. From STEREO/EUVI and STEREO/COR1 data, the full CME kinematics of the impulsive acceleration phase up to {approx}4 R{sub sun} is measured with a high time cadence of <=2.5 minutes. For deriving CME velocity and acceleration, we apply and test a new algorithm based on regularization methods. The CME maximum acceleration is achieved at heights h <= 0.4 R{sub sun}, and the peak velocity at h <= 2.1 R{sub sun} (in one case, as small as 0.5 R{sub sun}). We find that the CME acceleration profile and the flare energy release as evidenced in the RHESSI HXR flux evolve in a synchronized manner. These results support the 'standard' flare/CME model which is characterized by a feedback relationship between the large-scale CME acceleration process and the energy release in the associated flare.},
doi = {10.1088/0004-637X/712/2/1410},
journal = {Astrophysical Journal},
number = 2,
volume = 712,
place = {United States},
year = {Thu Apr 01 00:00:00 EDT 2010},
month = {Thu Apr 01 00:00:00 EDT 2010}
}
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