Irkutsk, Irkutsk region, Russian Federation
Irkutsk, Russian Federation
UDK 520 Астрономия. Астрофизика. Исследование космичечского пространства
GRNTI 41.51 Обсерватории. Инструменты, приборы и методы астрономических наблюдений
OKSO 03.06.01 Физика и астрономия
BBK 22 Физико-математические науки
TBK 614 Астрономия
BISAC SCI076000 Scientific Instruments
The paper describes application of standard gain calibration using redundancy for a 48-antenna prototype of Siberian Radioheliograph. Traditionally, for calibration, the visibilities were measured only between adjacent antennas since they have the highest signal-to-noise ratio and are sufficient for phase calibration. We have shown that this limited set of visibilities did not allow using the antenna array redundancy potential and obtaining images with a high dynamic range on a permanent basis. Images without amplitude calibration contain many artifacts and require special care when analyzed. The inclusion of visibility measurement between antennas with a double step made it possible to significantly increase the accuracy of solving the system of equations for amplitudes. Images constructed using both phase and amplitude calibrations do not have visible artifacts and are more reliable.
solar radio telescope, visibility function, radio interferometer, gain calibration
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