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Title: Investigation of Relationship between High-energy X-Ray Sources and Photospheric and Helioseismic Impacts of X1.8 Solar Flare of 2012 October 23

Abstract

The X-class solar flare of 2012 October 23 generated continuum photospheric emission and a strong helioseismic wave (“sunquake”) that points to an intensive energy release in the dense part of the solar atmosphere. We study properties of the energy release with high temporal and spatial resolutions, using photospheric data from the Helioseismic Magnetic Imager (HMI) on board Solar Dynamics Observatory , and hard X-ray observations made by RHESSI . For this analysis we use level-1 HMI data (filtergrams), obtained by scanning the Fe i line (6731 Å) with the time cadence of ∼3.6 s and spatial resolution of ∼0.″5 per pixel. It is found that the photospheric disturbances caused by the flare spatially coincide with the region of hard X-ray emission but are delayed by ≲4 s. This delay is consistent with predictions of the flare hydrodynamics RADYN models. However, the models fail to explain the magnitude of variations observed by the HMI. The data indicate that the photospheric impact and helioseismic wave might be caused by the electron energy flux, which is substantially higher than that in the current flare radiative hydrodynamic models.

Authors:
;  [1]; ;  [2];  [3]
  1. Space Research Institute (IKI) of the Russian Academy of Sciences, Moscow (Russian Federation)
  2. New Jersey Institute of Technology, Newark, NJ (United States)
  3. Institute of Solar-Terrestrial Research (ISTP) of the Russian Academy of Sciences, Siberian Branch, Irkutsk (Russian Federation)
Publication Date:
OSTI Identifier:
22663429
Resource Type:
Journal Article
Resource Relation:
Journal Name: Astrophysical Journal; Journal Volume: 843; 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; CHROMOSPHERE; COSMIC X-RAY SOURCES; DISTURBANCES; ELECTRONS; EMISSION; FORECASTING; HARD X RADIATION; HYDRODYNAMIC MODEL; HYDRODYNAMICS; MAGNETIC FIELDS; PHOTOSPHERE; SOLAR FLARES; SPATIAL RESOLUTION; SUN; X-RAY SOURCES

Citation Formats

Sharykin, I. N., Zimovets, I. V., Kosovichev, A. G., Sadykov, V. M., and Myshyakov, I. I., E-mail: ivan.sharykin@phystech.edu. Investigation of Relationship between High-energy X-Ray Sources and Photospheric and Helioseismic Impacts of X1.8 Solar Flare of 2012 October 23. United States: N. p., 2017. Web. doi:10.3847/1538-4357/AA77F1.
Sharykin, I. N., Zimovets, I. V., Kosovichev, A. G., Sadykov, V. M., & Myshyakov, I. I., E-mail: ivan.sharykin@phystech.edu. Investigation of Relationship between High-energy X-Ray Sources and Photospheric and Helioseismic Impacts of X1.8 Solar Flare of 2012 October 23. United States. doi:10.3847/1538-4357/AA77F1.
Sharykin, I. N., Zimovets, I. V., Kosovichev, A. G., Sadykov, V. M., and Myshyakov, I. I., E-mail: ivan.sharykin@phystech.edu. Sat . "Investigation of Relationship between High-energy X-Ray Sources and Photospheric and Helioseismic Impacts of X1.8 Solar Flare of 2012 October 23". United States. doi:10.3847/1538-4357/AA77F1.
@article{osti_22663429,
title = {Investigation of Relationship between High-energy X-Ray Sources and Photospheric and Helioseismic Impacts of X1.8 Solar Flare of 2012 October 23},
author = {Sharykin, I. N. and Zimovets, I. V. and Kosovichev, A. G. and Sadykov, V. M. and Myshyakov, I. I., E-mail: ivan.sharykin@phystech.edu},
abstractNote = {The X-class solar flare of 2012 October 23 generated continuum photospheric emission and a strong helioseismic wave (“sunquake”) that points to an intensive energy release in the dense part of the solar atmosphere. We study properties of the energy release with high temporal and spatial resolutions, using photospheric data from the Helioseismic Magnetic Imager (HMI) on board Solar Dynamics Observatory , and hard X-ray observations made by RHESSI . For this analysis we use level-1 HMI data (filtergrams), obtained by scanning the Fe i line (6731 Å) with the time cadence of ∼3.6 s and spatial resolution of ∼0.″5 per pixel. It is found that the photospheric disturbances caused by the flare spatially coincide with the region of hard X-ray emission but are delayed by ≲4 s. This delay is consistent with predictions of the flare hydrodynamics RADYN models. However, the models fail to explain the magnitude of variations observed by the HMI. The data indicate that the photospheric impact and helioseismic wave might be caused by the electron energy flux, which is substantially higher than that in the current flare radiative hydrodynamic models.},
doi = {10.3847/1538-4357/AA77F1},
journal = {Astrophysical Journal},
number = 1,
volume = 843,
place = {United States},
year = {Sat Jul 01 00:00:00 EDT 2017},
month = {Sat Jul 01 00:00:00 EDT 2017}
}
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