Solar Physics

, 293:62 | Cite as

Oscillations and Waves in Radio Source of Drifting Pulsation Structures

  • Marian Karlický
  • Ján Rybák
  • Miroslav Bárta


Drifting pulsation structures (DPSs) are considered to be radio signatures of the plasmoids formed during magnetic reconnection in the impulsive phase of solar flares. In the present paper we analyze oscillations and waves in seven examples of drifting pulsation structures, observed by the 800 – 2000 MHz Ondřejov Radiospectrograph. For their analysis we use a new type of oscillation maps, which give us much more information as regards processes in DPSs than that in previous analyses. Based on these oscillation maps, made from radio spectra by the wavelet technique, we recognized quasi-periodic oscillations with periods ranging from about 1 to 108 s in all studied DPSs. This strongly supports the idea that DPSs are generated during a fragmented magnetic reconnection. Phases of most the oscillations in DPSs, especially for the period around 1 s, are synchronized (“infinite” frequency drift) in the whole frequency range of DPSs. For longer periods in some DPSs we found that the phases of the oscillations drift with the frequency drift in the interval from −17 to \(+287~\mbox{MHz}\,\mbox{s}^{-1}\). We propose that these drifting phases can be caused (a) by the fast or slow magnetosonic waves generated during the magnetic reconnection and propagating through the plasmoid, (b) by a quasi-periodic structure in the plasma inflowing to the reconnection forming a plasmoid, and (c) by a quasi-periodically varying reconnection rate in the X-point of the reconnection close to the plasmoid.


Sun: flares Sun: radio radiation Sun: oscillations 



This research was supported by Grants 16-13277S and 17-16447S of the Grant Agency of the Czech Republic. This work was supported by the Science Grant Agency project VEGA 2/0004/16 (Slovakia). Help of the Bilateral Mobility Projects SAV-16-03 and SAV-18-01 of the SAS and CAS is acknowledged. This article was created in the project ITMS No. 26220120029, based on the supporting operational Research and development program financed from the European Regional Development Fund. This research has made use of NASA’s Astrophysics Data System. The wavelet analysis was performed with software based on tools provided by C. Torrence and G.P. Compo at .

Disclosure of Potential Conflicts of Interest

The authors declare that they have no conflicts of interest.


  1. Bárta, M., Karlický, M., Žemlička, R.: 2008, Plasmoid dynamics in flare reconnection and the frequency drift of the drifting pulsating structure. Solar Phys. 253, 173. DOI. ADS. ADSCrossRefGoogle Scholar
  2. Bárta, M., Vršnak, B., Karlický, M.: 2008, Dynamics of plasmoids formed by the current sheet tearing. Astron. Astrophys. 477, 649. DOI. ADS. ADSCrossRefzbMATHGoogle Scholar
  3. Bárta, M., Büchner, J., Karlický, M., Skála, J.: 2011, Spontaneous current-layer fragmentation and cascading reconnection in solar flares. I. Model and analysis. Astrophys. J. 737, 24. DOI. ADS. ADSCrossRefGoogle Scholar
  4. Bárta, M., Karlický, M., Vršnak, B., Goossens, M.: 2007, MHD waves and shocks generated during magnetic field reconnection. Cent. Eur. Astrophys. Bull. 31. ADS.
  5. Dabrowski, B.P., Karlický, M., Rudawy, P.: 2015, Fourier analysis of radio bursts observed with very high time resolution. Solar Phys. 290, 169. DOI. ADS. ADSCrossRefGoogle Scholar
  6. Farge, M.: 1992, Wavelet transforms and their applications to turbulence. Annu. Rev. Fluid Mech. 24, 395. DOI. ADS. ADSMathSciNetCrossRefzbMATHGoogle Scholar
  7. Jelínek, P., Karlický, M., Van Doorsselaere, T., Bárta, M.: 2017, Oscillations excited by plasmoids formed during magnetic reconnection in a vertical gravitationally stratified current sheet. Astrophys. J. 847, 98. DOI. ADS. ADSCrossRefGoogle Scholar
  8. Jiřička, K., Karlický, M.: 2008, Narrowband pulsating decimeter structure observed by the new Ondřejov Solar Radio Spectrograph. Solar Phys. 253, 95. DOI. ADS. ADSCrossRefGoogle Scholar
  9. Karlický, M.: 2008, Separation of accelerated electrons and positrons in the relativistic reconnection. Astrophys. J. 674, 1211. DOI. ADS. ADSCrossRefGoogle Scholar
  10. Karlický, M.: 2013, Radio continua modulated by waves: zebra patterns in solar and pulsar radio spectra? Astron. Astrophys. 552, A90. DOI. ADS. ADSCrossRefGoogle Scholar
  11. Karlický, M.: 2014, Solar flares: radio and X-ray signatures of magnetic reconnection processes. Res. Astron. Astrophys. 14, 753. DOI. ADS. ADSCrossRefGoogle Scholar
  12. Karlický, M., Bárta, M.: 2007, Drifting pulsating structures generated during tearing and coalescence processes in a flare current sheet. Astron. Astrophys. 464, 735. DOI. ADS. ADSCrossRefGoogle Scholar
  13. Karlický, M., Bárta, M.: 2011, Successive merging of plasmoids and fragmentation in a flare current sheet and their X-ray and radio signatures. Astrophys. J. 733, 107. DOI. ADS. ADSCrossRefGoogle Scholar
  14. Karlický, M., Bárta, M., Rybák, J.: 2010, Radio spectra generated during coalescence processes of plasmoids in a flare current sheet. Astron. Astrophys. 514, A28. DOI. ADS. CrossRefGoogle Scholar
  15. Karlický, M., Kliem, B.: 2010, Reconnection of a kinking flux rope triggering the ejection of a microwave and hard X-ray source I. Observations and interpretation. Solar Phys. 266, 71. DOI. ADS. ADSCrossRefGoogle Scholar
  16. Karlický, M., Mészárosová, H., Jelínek, P.: 2013, Radio fiber bursts and fast magnetoacoustic wave trains. Astron. Astrophys. 550, A1. DOI. ADS. CrossRefGoogle Scholar
  17. Karlický, M., Rybák, J.: 2017, Oscillation maps in the broadband radio spectrum of the 1 August 2010 event. Solar Phys. 292, 1. DOI. ADS. ADSCrossRefGoogle Scholar
  18. Karlický, M., Rybák, J., Monstein, C.: 2017, Oscillations in the 45 – 5000 MHz radio spectrum of the 18 April 2014 flare. Solar Phys. 292, 94. DOI. ADS. ADSCrossRefGoogle Scholar
  19. Karlický, M., Bárta, M., Mészárosová, H., Zlobec, P.: 2005, Time scales of the slowly drifting pulsating structure observed during the April 12, 2001 flare. Astron. Astrophys. 432, 705. DOI. ADS. ADSCrossRefGoogle Scholar
  20. Kliem, B., Karlický, M., Benz, A.O.: 2000, Solar flare radio pulsations as a signature of dynamic magnetic reconnection. Astron. Astrophys. 360, 715. ADS. ADSGoogle Scholar
  21. Loureiro, N.F., Schekochihin, A.A., Cowley, S.C.: 2007, Instability of current sheets and formation of plasmoid chains. Phys. Plasmas 14(10), 100703. DOI. ADS. ADSCrossRefGoogle Scholar
  22. Ohyama, M., Shibata, K.: 1998, X-ray plasma ejection associated with an impulsive flare on 1992 October 5: physical conditions of X-ray plasma ejection. Astrophys. J. 499, 934. DOI. ADS. ADSCrossRefGoogle Scholar
  23. Torrence, C., Compo, G.P.: 1998, A practical guide to wavelet analysis. Bull. Am. Meteorol. Soc. 79, 61. DOI. ADS. ADSCrossRefGoogle Scholar

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© Springer Science+Business Media B.V., part of Springer Nature 2018

Authors and Affiliations

  1. 1.Astronomical InstituteAcademy of Sciences of the Czech RepublicOndřejovCzech Republic
  2. 2.Astronomical InstituteSlovak Academy of SciencesTatranská LomnicaSlovakia

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