Abstract
We present the results of solar observations at 20 and 25 MHz with the Ukrainian T-shaped Radio telescope of the second modification (UTR-2) in the interferometric session from 27 May to 2 June 2014. In this case, the different baselines 225, 450, and 675 m between the sections of the east–west and north–south arms of UTR-2 were used. On 29 May 2014, strong sporadic radio emission consisting of Type III, Type II, and Type IV bursts was observed. On other days, there was no solar radio activity in the decameter range. We discuss the observation results of the quiet Sun. Fluxes and sizes of the Sun in east–west and north–south directions were measured. The average fluxes were 1050 – 1100 Jy and 1480 – 1570 Jy at 20 and 25 MHz, respectively. The angular sizes of the quiet Sun in equatorial and polar directions were \(55'\) and \(49'\) at 20 MHz and \(50'\) and \(42'\) at 25 MHz. The brightness temperatures of the radio emission were \({T_{\mathrm{b}}} = 5.1 \times{10^{5}}~\mbox{K}\) and \({T_{\mathrm{b}}} = 5.7 \times{10^{5}}~\mbox{K}\) at 20 and 25 MHz, respectively.
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The work was partially financed in the frame of FP7 project SOLSPANET (FP7-PEOPLE-2010-IRSES-269299).
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Melnik, V.N., Shepelev, V.A., Poedts, S. et al. Interferometric Observations of the Quiet Sun at 20 and 25 MHz in May 2014. Sol Phys 293, 97 (2018). https://doi.org/10.1007/s11207-018-1316-3
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DOI: https://doi.org/10.1007/s11207-018-1316-3