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It is intended to use the mode of
sequential obtaining of images at different
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frequencies
in order to study coronal magnetic fields, in addressing problems of
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predicting
solar activity, and in investigating low-contrast structures such as
coronal
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holes
and filaments. Coronal mass ejections are commonly characterized by the
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angular
size as large as several tens of min of arc. Therefore, it is more
appropriate to
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investigate
such phenomena in the mode of sequential obtaining full solar images at
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different
frequencies. Observations of ejections in the mode of simultaneous
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obtaining
a full solar image are appropriate only when accompanied by fast
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occurring
processes. For investigating the dynamics of solar activity (flares and,
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possibly,
coronal mass ejections), it is intended to use the mode of simultaneous
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obtaining
of a full solar image at 5.7 GHz
frequency and high spatial harmonics of
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corresponding
images at the other wavelengths. A tentative configuration of antennas
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for
this mode is illustrated in Fig. 6. The field of view for frequencies above
5.7 GHz
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in
this case will be reduced to a few min of arc. This should not have a
substantial
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influence
on the observations of flares as a consequence of their small angular size.
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However,
in observations of coronal mass ejections, such a limitation could have a
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serious
influence.
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It should be noted that the question
as to the selection of the antenna
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configuration
for simultaneous obtaining of images at different frequencies is open.
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It
seems most likely that it will be answered in the process of observations.
For this it
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is
important that the whole instrument has a sufficient flexibility. Such a
flexibility is
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ensured
by equipping each antenna with a controlled multiwave receiver and by the
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control
of the process of calculating cross-correlation functions of signals
received
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from antennas.
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