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Title: AN INTERPRETATION OF GLE71 CONCURRENT CME-DRIVEN SHOCK WAVE

Abstract

Particle accelerations in solar flares and CME-driven shocks can sometimes result in very high-energy particle events (≥1 GeV) that are known as ground level enhancements (GLEs). Recent studies on the first GLE event (GLE71 2012 May 17 01:50 UT) of solar cycle 24 suggested that CME-driven shock played a leading role in causing the event. To verify this claim, we have made an effort to interpret the GLE71 concurrent shock wave. For this, we have deduced the possible speed and height of the shock wave in terms of the frequency (MHz) of the solar radio type II burst and its drift rate (MHz min{sup –1}), and studied the temporal evolution of the particle intensity profiles at different heights of the solar corona. For a better perception of the particle acceleration in the shock, we have studied the solar radio type II burst with concurrent solar radio and electron fluxes. When the particle intensity profiles are necessarily shifted in time at ∼1 AU, it is found that the growth phases of the electron and cosmic ray intensity fluxes are strongly correlated (>0.91; ≥0.87) with the frequency drift rate of the type II burst, which is also consistent with the intensive particlemore » accelerations at upper coronal heights (∼≥0.80 R {sub S} < 1.10 R {sub S}). Thus, we conclude that the CME-driven shock was possibly capable of producing the high-energy particle event. However, since the peaks of some flare components are found to be strongly associated with the fundamental phase of the type II burst, the preceding flare is supposed to contribute to the shock acceleration process.« less

Authors:
;  [1]; ; ;  [2];  [3];  [4];  [5];  [6]
  1. Space Research Group, Universidad de Alcalá, E-28871 Alcalá de Henares (Spain)
  2. Key Laboratory of Dark Matter and Space Astronomy, Purple Mountain Observatory, Chinese Academy of Sciences, 210008 Nanjing (China)
  3. School of Space Science, Kyung-Hee University, 446-701 Yongin-Si, Gyeonggi-do (Korea, Republic of)
  4. Institute of Experimental Physics, Slovak Academy of Sciences, Watsonova 47, 04001 Kosice (Slovakia)
  5. Korea Astronomy and Space Science Institute, Daejeon 305-348 (Korea, Republic of)
  6. Israel Cosmic Ray and Space Weather Center with Emilio Segré Observatory on Mt. Hermon, Tel Aviv University, Golan Research Institute, Israel Space Agency (Israel)
Publication Date:
OSTI Identifier:
22340188
Resource Type:
Journal Article
Resource Relation:
Journal Name: Astrophysical Journal, Supplement Series; Journal Volume: 213; Journal Issue: 2; Other Information: Country of input: International Atomic Energy Agency (IAEA)
Country of Publication:
United States
Language:
English
Subject:
79 ASTROPHYSICS, COSMOLOGY AND ASTRONOMY; ACCELERATION; COSMIC RADIATION; ELECTRONS; GEV RANGE; GROUND LEVEL; MHZ RANGE; SHOCK WAVES; SOLAR CORONA; SOLAR CYCLE; SOLAR FLARES; VELOCITY

Citation Formats

Firoz, Kazi A., Rodríguez-Pacheco, J., Zhang, Q. M., Gan, W. Q., Li, Y. P., Moon, Y.-J., Kudela, K., Park, Y.-D., and Dorman, Lev I., E-mail: kazifiroz2002@gmail.com, E-mail: firoz.kazi@uah.es. AN INTERPRETATION OF GLE71 CONCURRENT CME-DRIVEN SHOCK WAVE. United States: N. p., 2014. Web. doi:10.1088/0067-0049/213/2/24.
Firoz, Kazi A., Rodríguez-Pacheco, J., Zhang, Q. M., Gan, W. Q., Li, Y. P., Moon, Y.-J., Kudela, K., Park, Y.-D., & Dorman, Lev I., E-mail: kazifiroz2002@gmail.com, E-mail: firoz.kazi@uah.es. AN INTERPRETATION OF GLE71 CONCURRENT CME-DRIVEN SHOCK WAVE. United States. doi:10.1088/0067-0049/213/2/24.
Firoz, Kazi A., Rodríguez-Pacheco, J., Zhang, Q. M., Gan, W. Q., Li, Y. P., Moon, Y.-J., Kudela, K., Park, Y.-D., and Dorman, Lev I., E-mail: kazifiroz2002@gmail.com, E-mail: firoz.kazi@uah.es. Fri . "AN INTERPRETATION OF GLE71 CONCURRENT CME-DRIVEN SHOCK WAVE". United States. doi:10.1088/0067-0049/213/2/24.
@article{osti_22340188,
title = {AN INTERPRETATION OF GLE71 CONCURRENT CME-DRIVEN SHOCK WAVE},
author = {Firoz, Kazi A. and Rodríguez-Pacheco, J. and Zhang, Q. M. and Gan, W. Q. and Li, Y. P. and Moon, Y.-J. and Kudela, K. and Park, Y.-D. and Dorman, Lev I., E-mail: kazifiroz2002@gmail.com, E-mail: firoz.kazi@uah.es},
abstractNote = {Particle accelerations in solar flares and CME-driven shocks can sometimes result in very high-energy particle events (≥1 GeV) that are known as ground level enhancements (GLEs). Recent studies on the first GLE event (GLE71 2012 May 17 01:50 UT) of solar cycle 24 suggested that CME-driven shock played a leading role in causing the event. To verify this claim, we have made an effort to interpret the GLE71 concurrent shock wave. For this, we have deduced the possible speed and height of the shock wave in terms of the frequency (MHz) of the solar radio type II burst and its drift rate (MHz min{sup –1}), and studied the temporal evolution of the particle intensity profiles at different heights of the solar corona. For a better perception of the particle acceleration in the shock, we have studied the solar radio type II burst with concurrent solar radio and electron fluxes. When the particle intensity profiles are necessarily shifted in time at ∼1 AU, it is found that the growth phases of the electron and cosmic ray intensity fluxes are strongly correlated (>0.91; ≥0.87) with the frequency drift rate of the type II burst, which is also consistent with the intensive particle accelerations at upper coronal heights (∼≥0.80 R {sub S} < 1.10 R {sub S}). Thus, we conclude that the CME-driven shock was possibly capable of producing the high-energy particle event. However, since the peaks of some flare components are found to be strongly associated with the fundamental phase of the type II burst, the preceding flare is supposed to contribute to the shock acceleration process.},
doi = {10.1088/0067-0049/213/2/24},
journal = {Astrophysical Journal, Supplement Series},
number = 2,
volume = 213,
place = {United States},
year = {Fri Aug 01 00:00:00 EDT 2014},
month = {Fri Aug 01 00:00:00 EDT 2014}
}
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