Abstract
25 MHz–7.6 GHz global and detailed (fine structure – FS) radio spectra are presented, which were observed in the NOAA 9077 active region for the Bastille Day (14 July 2000) flare at 10:10–11:00 UT. Besides broadband radio bursts, high-resolution dynamic spectra reveal metric type II burst, decimetric type IV burst and various decimetric and microwave FSs, such as type III bursts, type U bursts, reverse-slope (RS)-drifting burst, fiber bursts, patch and drifting pulsation structure (DPS). The peak-flux-density spectrum of the radio bursts over the range 1.0–7.6 GHz globally appears as a U-shaped signature. Analyzing the features of backbone and herringbones of the type II burst, the speeds of shock and relevant energetic electron beams were estimated to be 1100 km s−1 and 58 500 km s−1, respectively. Also the time sequence of the radio emission is analyzed by comparing with the hard X-rays (HXRs) and the soft X-rays (SXRs) in this flare. After the maxima of the X-rays, the radio emission in the range 1.0–7.6 GHz reached maxima first at the higher frequency, then drifted to the lower frequency. This comparison suggested that the flare included three successive processes: firstly the X-rays rose and reached maxima at 10:10–10:23 UT, accompanied by fine structures only in the range 2.6–7.6 GHz; secondly the microwave radio emission reached maxima accompanied by many fine structures over the range 1.0–7.6 GHz at 10:23–10:34 UT; then a decimetric type IV burst and its associated FSs (fibers) in the range 1.0–2.0 GHz appeared after 10:40 UT.
This is a preview of subscription content, log in via an institution to check access.
Similar content being viewed by others
References
Allaart, M. A. F., Van Nieuwkoop, J., Slottje, C., and Sondaar, L. H.: 1990, Solar Phys. 130, 183.
Bastian, T. S., Benz, A. O., and Gary, D. E.: 1998, Ann. Rev. Astron. Astrophys. 36, 131.
Benz, A. O.: 1986, Solar Phys. 104, 99.
Benz, A. O.: 1993, Plasma Astrophysics, Kluwer Academic Publishers, Netherlands.
Caroubalos, C., Alissandraskis, C. E., Hillaris, A., Nindos, A., Tsitsipis, P., Moussas, X. et al.: 2001, Solar Phys., this issue.
Chertok, I. M., Fomichev, V. V., Gnezdilov, A. A., Gorgutsa, R. V., Grechnev, V. V., Markeev, A. K. et al.: 2001, Solar Phys., this issue.
Dröge, F.: 1977, Astron. Astrophys. 57, 285.
Fu, Q. J., Qin, Z. H., Ji, H. R., and Pei, L. B.: 1995, Solar Phys. 160, 97.
Guidice, D. A. and Castelli, J. P.: 1975, Solar Phys. 44, 155.
Lin, H. A., Zhu, G. W., Wang, S. J.: 2000, Chinese J. Space Sci. 20, 251.
Isliker, H. and Benz, A. O.: 1994, Astron. Astrophys. Suppl. Ser. 104, 145.
Karlický, M., Yan, Y.H., Fu, Q.J., Wang,S.J.,Jiřička, K., Mészárosová, H., and Liu, Y. Y.: 2001, Astron. Astrophys. 369, 1104.
Kliem, B., Karlický, M., Benz, A. O.: 2000, Astron. Astrophys. 360, 715.
Kopp, R. A. and Pneuman, G.: 1976, Solar Phys. 50, 85.
Kundu, M. R.: 1965, Solar Radio Astronomy, Interscience Publishers, New York.
Kundu, M. R. and Vlahos, L.: 1982, Space Sci. Rev. 32, 405.
Mann, G. and Classen, H. T.: 1995, Astron. Astrophys. 304, 576.
Nelson, G. S. and Melrose, D. B.: 1985, in Mclean, D. J. and Labrum, N. R. (eds.), Solar Radiophysics, Cambridge University Press, Cambridge, UK, p. 333.
Slottje, C.: 1978, Nature 275, 520.
Wang, S. J., Yan Y. H., Fu, Q. J.: 2001, Astron. Astrophys. 370, L13.
Wild, J. P., Smerd, S. F., and Weiss, A. A.: 1963, Ann. Rev. Astron. Astrophys. 1, 291.
Yan, Y. H., Deng, Y. Y., Karlický, M., Fu, Q. J., Wang, S. J., Liu, Y. Y.: 2001a, Astrophys. J 551, L115.
Yan, Y. H., Aschwanden, M. J., Wang, S. J., Deng, Y. Y.,: 2001b, Solar Phys., this issue.
Author information
Authors and Affiliations
Rights and permissions
About this article
Cite this article
Wang, S., Yan, Y., Zhao, R. et al. Broadband Radio Bursts and Fine Structures during the Great Solar Event on 14 July 2000. Sol Phys 204, 153–164 (2001). https://doi.org/10.1023/A:1014278511984
Issue Date:
DOI: https://doi.org/10.1023/A:1014278511984