Abstract
Using the double-plasma resonance model of solar radio zebras, we analyze five models of the magnetic field and density in the zebra source region. We present analytical relations of zebra-stripe frequencies depending on the gyro-harmonic number. By fitting of observed zebra-stripe frequencies using model frequencies, we find that the determined gyro-harmonic number and corresponding magnetic field depend on the model used. We show that all previously analyzed zebras, where the absolute value of the difference between neighboring zebra-stripe frequencies increases with respect to increasing frequency, can be well fitted by the model with exponential dependencies of the magnetic field and density or by the model with smaller gradients of both of these variables. Although these models give different results, their more sophisticated versions give more similar results. We also present the models that can fit the zebras, if observed, where the absolute value of the difference between neighboring zebra-stripe frequencies decreases with respect to increasing frequency. We check all these models by a fitting of the zebra-stripe frequencies observed in the 21 June 2011 zebra event. In one model, although it reasonably describes the conditions in the atmosphere above the active region, the fit of the observed zebra-stripe frequencies could not be made.
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The datasets generated during and/or analyzed during the current study are available from the corresponding author on reasonable request.
References
Aschwanden, M.J., Benz, A.O.: 1995, Chromospheric evaporation and decimetric radio emission in solar flares. Astrophys. J. 438, 997. DOI. ADS.
Chen, B., Bastian, T.S., Gary, D.E., Jing, J.: 2011, Spatially and spectrally resolved observations of a Zebra pattern in a solar decimetric radio burst. Astrophys. J. 736, 64. DOI. ADS.
Chernov, G.: 2011, Fine Structure of Solar Radio Bursts, Astrophys. Space Scien. Lib. Springer, Heidelberg. ADS.
Chernov, G.P.: 2006, Solar radio bursts with drifting stripes in emission and absorption. Space Sci. Rev. 127, 195. DOI. ADS.
Dulk, G.A., McLean, D.J.: 1978, Coronal magnetic fields. Solar Phys. 57, 279. DOI. ADS.
Kaneda, K., Misawa, H., Iwai, K., Masuda, S., Tsuchiya, F., Katoh, Y., Obara, T.: 2018, Detection of propagating fast sausage waves through detailed analysis of a Zebra-pattern fine structure in a solar radio burst. Astrophys. J. Lett. 855, L29. DOI. ADS.
Karlický, M.: 2022, Simulations of solar radio zebras. Astron. Astrophys. 661, A56. DOI. ADS.
Karlický, M., Yasnov, L.V.: 2018, Determination of plasma parameters in radio sources of solar Zebra-patterns based on relations between the Zebra-stripe frequencies and gyro-harmonic numbers. Astrophys. J. 867, 28. DOI. ADS.
Klimchuk, J.A.: 2000, Cross-sectional properties of coronal loops. Solar Phys. 193, 53. DOI. ADS.
Kuijpers, J.: 1980, Theory of type IV DM bursts. In: Kundu, M.R., Gergely, T.E. (eds.): Radio Physics of the Sun, IAU Symp. 86, 341. ADS.
Kuijpers, J.M.E.: 1975, Collective wave-particle interactions in solar type IV radio sources. PhD thesis, Utrecht, Rijksuniversiteit, Doctor in de Wiskunde en Natuurwetenschappen Dissertation. 1975, 72 p. ADS.
Kuznetsov, A.A., Tsap, Y.T.: 2007, Loss-cone instability and formation of zebra patterns in type IV solar radio bursts. Solar Phys. 241, 127. DOI. ADS.
Mollwo, L.: 1983, Interpretation of patterns of drifting ZEBRA stripes. Solar Phys. 83, 305. DOI. ADS.
Mollwo, L.: 1988, The magneto-hydrostatic field in the region of ZEBRA patterns in solar type IV dm-bursts. Solar Phys. 116, 323. DOI. ADS.
Priest, E.: 2014, Magnetohydrodynamics of the Sun, Cambridge University Press, UK. ADS.
Slottje, C.: 1981, Atlas of Fine Structures of Dynamics Spectra of Solar Type IV-dm and Some Type II Radio Bursts. Dwingeloo Observatory, The Netherlands. ADS.
Tan, B., Yan, Y., Tan, C., Sych, R., Gao, G.: 2012, Microwave Zebra pattern structures in the X2.2 solar flare on 2011 February 15. Astrophys. J. 744, 166. DOI. ADS.
Tan, B., Tan, C., Zhang, Y., Mészárosová, H., Karlický, M.: 2014, Statistics and classification of the microwave zebra patterns associated with solar flares. Astrophys. J. 780, 129. DOI. ADS.
Winglee, R.M., Dulk, G.A.: 1986, The electron-cyclotron maser instability as a source of plasma radiation. Astrophys. J. 307, 808. DOI. ADS.
Yasnov, L.V.: 2021, On the magnetoacoustic waves and physical conditions in Zebra radio sources. Solar Phys. 296, 139. DOI. ADS.
Yasnov, L.V., Chernov, G.P.: 2020, Alternative models of Zebra patterns in the event on June 21, 2011. Solar Phys. 295, 13. DOI. ADS.
Yasnov, L.V., Karlický, M.: 2020, Magnetic field, electron density and their spatial scales in Zebra pattern radio sources. Solar Phys. 295, 96. DOI. ADS.
Yu, S., Yan, Y., Tan, B.: 2012, Relaxation of magnetic field relative to plasma density revealed from microwave Zebra patterns associated with solar flares. Astrophys. J. 761, 136. DOI. ADS.
Zheleznyakov, V.V., Zlotnik, E.Y.: 1975, Cyclotron wave instability in the corona and origin of solar radio emission with fine structure. III. Origin of zebra-pattern. Solar Phys. 44, 461. DOI. ADS.
Zheleznyakov, V.V., Zlotnik, E.Y., Zaitsev, V.V., Shaposhnikov, V.E.: 2016, Double plasma resonance and its manifestations in radio astronomy. Phys. Usp. 59, 997. DOI. ADS.
Zlotnik, E.Y., Zaitsev, V.V., Aurass, H., Mann, G., Hofmann, A.: 2003, Solar type IV burst spectral fine structures. II. Source model. Astron. Astrophys. 410, 1011. DOI. ADS.
Acknowledgments
M. Karlický acknowledges support from the project RVO-67985815 and GA ČR grants 20-09922J, 20-07908S, 21-16508J and 22-34841S. L.V. Yasnov acknowledges support from the Russian Foundation for Basic Research, Grant 18-29- 21016.
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L. Y. made all computations. M. K. prepared the English version of the manuscript. Both authors reviewed the manuscript.
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Yasnov, L.V., Karlický, M. Magnetic Field and Density Models in the Zebra Source Region. Sol Phys 297, 133 (2022). https://doi.org/10.1007/s11207-022-02067-5
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DOI: https://doi.org/10.1007/s11207-022-02067-5