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Solar Microwave Emission in Active Regions

Published online by Cambridge University Press:  04 August 2017

B. Lokanadham
Affiliation:
Department of Astronomy, Osmania University, Hyderabad
P. K. Subramanian
Affiliation:
Department of Astronomy, Osmania University, Hyderabad
M. Sateesh Reddy
Affiliation:
Department of Astronomy, Osmania University, Hyderabad
B. M. Reddy
Affiliation:
National Physical Research Laboratory, New Delhi, India
D. R. Lakshmi
Affiliation:
National Physical Research Laboratory, New Delhi, India

Abstract

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Multi–frequency Observations of Solar Microwave bursts recorded during solar maximum period 1980–81 are analysed and compared with x–ray data for studying the nature of microwave emissions from active regions. Most of the microwave burst spectra showed that the spectral index below the peak frequency is always less than 2.

The magneto-ionic conditions of the burst sources and the electron energies as obtained from these multi-frequency observations of the bursts showed that the centimetric and x-ray observations are satisfactorily explained, if the emitting regions are dense, hot and compact associated with strong magnetic fields of a few hundred gauss, suggesting that the thermal gyroresonance process is the most likely emission mechanism involved in the emission of microwave and x-ray radiations from the active regions of sun.

Type
Session III
Copyright
Copyright © Reidel 1985 

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