First temperature measurements over active regions have been obtained
based on an automatic iterative method applied to the data observed at
RATAN-600. The detection is based on observations of the polarized
radio emission at the RATAN-600 radio telescope and radio emission
calculations in the magnetic field extrapolated to the Solar corona
(according to the photospheric magnetogram SDO / HMI data).
To evaluate electronic temperature, we developed an iterative method
based on calculation of cyclotron radio emission in the range of
2-18 GHz, on convolution of radio maps with the diagram of the
telescope and comparison with the observed data at several tens
of wavelengths. The method has been applied for several active
regions with bright single spot sources with a high degree of
polarization at high frequencies (which indicates the cyclotron
radiation without significant heat braking contribution).
We have received temperature increase in the transition region and
lower corona being consistent, generally, with the adopted Selhorst
model based on individual characteristics of active regions. The
results are in a good agreement with direct measurements of the
magnetic field at the base of the corona from radio observations
(on the assumption of cyclotron radiation at the 2nd and 3rd harmonic
gyro frequency) and allow us to specify the height estimate for these
measurements.
Kaltman T.I., Bogod V.M. (SAO RAS) in collaboration with Stupishin A.G.,
Yasnov L.V. (SPbU)
Published:
Stupishin A., Bogod V., Kaltman T., Yasnov L., Modeling of solar
atmosphere parameters above the active region using RATAN-600
radiotelescope observation, Programme and abstracts of
CESRA 2016: Solar Radio Physics from the Chromosphere to
Near Earth 13-17 June 2016, Orleans (France), electronic issue, p. 100
Contact - Kaltman T.
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