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We report ground based, low frequency heliograph (80 MHz), spectral (85-35 MHz), and polarimeter (80 and 40 MHz) observations of drifting, non-thermal radio continuum associated with the “halo” coronal mass ejection that occurred in the solar atmosphere on 2013 March 15. The magnetic field strengths (B) near the radio source were estimated to be B ≈ 2.2 ± 0.4 G at 80 MHz and B ≈ 1.4 ± 0.2 G at 40 MHz. The corresponding radial distances (r) are r ≈ 1.9 R☼ (80 MHz) and r ≈ 2.2 R☼ (40 MHz). [ABSTRACT FROM AUTHOR]

We report ground-based, low-frequency (<100 MHz) radio imaging, spectral, and polarimeter observations of the type II radio burst associated with the solar coronal mass ejection (CME) that occurred on 2013 May 2. The spectral observations indicate that the burst has fundamental (F) and harmonic (H) emission components with split-band and herringbone structures. The imaging observations at 80 MHz indicate that the H component of the burst was located close to leading edge of the CME at a radial distance of r ≈ 2 R☼ in the solar atmosphere. The polarimeter observations of the type II burst, also at 80 MHz, indicate that the peak degree of circular polarization (dcp) corresponding to the emission generated in the corona ahead of and behind the associated MHD shock front are ≈0.05 ± 0.02 and ≈0.1 ± 0.01, respectively. We calculated the magnetic field B in the above two coronal regions by adopting the empirical relationship between the dcp and B for the harmonic plasma emission and the values are ≈(0.7-1.4) ± 0.2 G and ≈(1.4-2.8) ± 0.1 G, respectively. [ABSTRACT FROM AUTHOR]