Calculation of coronal magnetic field and density of nonthermal electrons

Huang Guangli

Using the theories of non-thermal gyro-synchrotron radiations, the author paid attention to the radio diagnosis of coronal magnetic field and non-thermal electrons in the source region of solar microwave bursts. A group of expressions of coronal magnetic field, the line-of-sight number of non-thermal electrons, and propagation angle as the explicit function of brightness temperature, frequency, turnover frequency, and spectral index were derived based on the approximation used by Dulk & Marsh (1982). It is shown that the calculated coronal magnetic field and line-of-sight number of non-thermal electrons is monotonously increasing or decreasing with frequency, turnover frequency, and brightness temperature in different range of spectral index. The value of propagation angle is always small. For a given spectral index, turnover frequency may play important role in the diagnosis of coronal magnetic field and non-thermal electrons.