The multifrequency Siberian Radioheliograph

摘要

The 10-antenna prototype of the multifrequency Siberian radioheliograph isdescribed. The prototype consists of four parts: antennas with broadbandfront-ends, analog back-ends, digital receivers and a correlator. The prototypeantennas are mounted on the outermost stations of the Siberian Solar RadioTelescope (SSRT) array. A signal from each antenna is transmitted to a workroomby an analog fiber optical link, laid in an underground tunnel. After mixing,all signals are digitized and processed by digital receivers before the dataare transmitted to the correlator. The digital receivers and the correlator areaccessible by the LAN. The frequency range of the prototype is from 4 to 8 GHz.Currently the frequency switching observing mode is used. The prototype datainclude both circular polarizations at a number of frequencies given by a list.This prototype is the first stage of the multifrequency Siberianradioheliograph development. It is assumed that the radioheliograph willconsist of 96 antennas and will occupy stations of the West-East-South subarrayof the SSRT. The radioheliograph will be fully constructed in autumn of 2012.We plan to reach the brightness temperature sensitivity about 100 K for thesnapshot image, a spatial resolution up to 13 arcseconds at 8 GHz andpolarization measurement accuracy about a few percent. First results with the 10-antenna prototype are presented of observations ofsolar microwave bursts. The prototype abilities to estimate source size andlocations at different frequencies are discussed.