Abstract
Occurrences of the flare-associated microwave bursts as well as their peak flux and energy excess spectra have been examined in relation to the pre- and post-maximum phases of the respective flares during the period 1969–72. Results obtained are: (i) about 76% of the flare-associated bursts occur in the pre-maximum phase and the remaining 24% occurs in the post-maximum phase irrespective of the flare classification, intensity-wise or area-wise; (ii) ‘impulsive’ and ‘gradual rise and fall’ bursts are relatively more important in the pre-maximum phase while ‘post burst increase’ bursts show comparatively higher occurrences in the post-maximum phase; (iii) peak flux and energy excess spectra of the concurrent microwave bursts in the pre-maximum phase of the flare are mostly of ‘inverted U’ and ‘increasing with frequency’ spectral types. Of these, ‘impulsive’ bursts are predominantly of the ‘inverted U’ and the ‘grf’ bursts are of the ‘increasing with frequency’ spectral type.
Similar content being viewed by others
References
Covington, A. E. and Harvey, G. A.: 1961,Nature 192, 152.
Ellison, M. A.: 1949,Monthly Notices Roy. Astron. Soc. 109, 3.
Harvey, K. L.: 1971,Solar Phys. 16, 423.
Sakurai, K.: 1966,Rep. Ionos. Space Res. Japan 20, 515.
SGD: 1974,Solar Geophysical Data, Descriptive Text, No. 354.
Author information
Authors and Affiliations
Rights and permissions
About this article
Cite this article
Sarkar, S.K., Chattopadhyay, T. & Das Gupta, M.K. Some studies on solar microwave bursts in relation to the phases of the associated Hα-flares and their spectral nature. Sol Phys 40, 411–415 (1975). https://doi.org/10.1007/BF00162387
Received:
Issue Date:
DOI: https://doi.org/10.1007/BF00162387