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arXiv · 2611.08195

Source Imaging of the Multiple Type-II Solar Radio Bursts and their Multiple CME-Shock Signatures in the Corona

V. Vasanth
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Abstract

This study reports the meter-wavelength radio imaging of multiple type-II bursts occurred on 01 October 2011 observed by LEARMONTH radio spectrograph in the frequency range of 180 - 25 MHz, with two coronal shocks from two coronal mass ejections (CMEs) from the nearby active regions lying adjacent to each other. The two CMEs are well observed by STEREO and LASCO FOV. The eruption is associated with the multi-peaked soft X-ray flare erupted from N16W45 (first and second C3 and C6 class flares) and from N09W04 (third one an M Class flare). The first type-II burst starts during the impulsive phase of the first flare and the second type-II burst starts during the peak time of the third flare. The drift rate of the second type-II burst is larger than that of the first type-II burst. The EUV images at AIA 211 reveal the shock-like EUV wave structure along the north-western limb around 09:06 UT, the first type-II appearing around the same time (09:06 UT) confirms the existence of the shock wave and as an outward propagating wave along the disk around 09:55 UT, the second type-II appearing around the same time (09:55 UT) confirms the existence of the shock wave. According to the simultaneous EUV and radio imaging data the radio sources appears along the nose-front of the shock like EUV wave structure for the first type-II burst and for the second type-II burst they are located along the shock flank. The study shows the possibility of two coronal shocks from two CMEs generating the multiple type-II radio bursts. The second event is strongly affected by the projection and scattering effects, the corrections are achieved by applying spherical cone model and 3D Monte Carlo ray-tracing code for turbulent solar environment at fundamental frequency.

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V. Vasanth. 2026-11-05. Source Imaging of the Multiple Type-II Solar Radio Bursts and their Multiple CME-Shock Signatures in the Corona. https://arxiv.org/abs/2611.08195

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