Related papers: CME liftoff with high-frequency fragmented type II…

Context. Coronal mass ejections (CMEs) on the Sun are the largest explosions in the Solar System that can drive powerful plasma shocks. The eruptions, shocks, and other processes associated to CMEs are efficient particle accelerators and…

In this paper, we study the formation and early evolution of a limb coronal mass ejection (CME) and its associated shock wave that occurred on 2014 January 8. The extreme ultraviolet (EUV) images provided by the Atmospheric Imaging Assembly…

We investigate the propagation of the 2015 June 21 CME-driven shock as revealed by the type II bursts at metric and longer wavelengths and coronagraph observations. The CME was associated with the second largest geomagnetic storm of solar…

The Sun regularly produces large-scale eruptive events, such as coronal mass ejections (CMEs) that can drive shock waves through the solar corona. Such shocks can result in electron acceleration and subsequent radio emission in the form of…

We discuss an intriguing type II radio burst that occurred on 2011 March 27. The dynamic spectrum was featured by a sudden break at about 43 MHz on the well-observed harmonic branch. Before the break, the spectrum drifted gradually with a…

Understanding electron acceleration associated with magnetic energy release at sub-second scales presents a major challenges in solar physics. Solar radio spikes observed as sub-second, narrow bandwidth bursts with…

A coronal mass ejection (CME) associated with a type II burst and originating close to the center of the solar disk typically results in a shock at Earth in 2-3 days and hence can be used to predict shock arrival at Earth. However, a…

We present the results of observations of complex powerful type II burst associated with narrow Earth-directed CME, which was ejected at around 11 UT on 31 May 2013. The observations were performed by radio telescope UTR-2, which operated…

A gradual solar energetic particle (SEP) event is thought to happen when particles are accelerated at a shock due to a fast coronal mass ejection (CME). To quantify what kind of solar eruptions can result in such SEP events, we have…

We show examples of excitation of coronal waves by flare-related abrupt eruptions of magnetic rope structures. The waves presumably rapidly steepened into shocks and freely propagated afterwards like decelerating blast waves that showed up…

Simultaneous radio and extreme ultraviolet (EUV)/white-light imaging data are examined for a solar type II radio burst occurring on 2010 March 18 to deduce its source location. Using a bow-shock model, we reconstruct the 3-dimensional EUV…

We simulate possible stellar coronal mass ejection (CME) scenarios over the magnetic cycle of $\epsilon$ Eridani (18 Eridani; HD 22049). We use three separate epochs from 2008, 2011, and 2013, and estimate the radio emission frequencies…

An interplanetary (IP) type-II-like radio burst is analyzed. It occurred on 2003 June 17-18 in association with a fast halo coronal mass ejection (CME), an M6.8 soft-X-ray (SXR) flare, and produced a solar proton event. Unlike coronal type…

Type II radio bursts are the indicator of adverse space weather in a stellar system. These radio bursts are the consequence of shock wave acceleration due to the coronal mass ejection (CME). In this study, we conduct a series of…

Band split of solar type II radio bursts, discovered several decades ago, is a fascinating phenomenon with the type-II lanes exhibiting two almost-parallel sub-bands with similar morphology. The underlying split mechanism remains elusive.…

A number of metric (100-650 MHz) typeII bursts was recorded by the ARTEMIS-IV radiospectrograph in the 1998-2000 period; the sample includes both CME driven shocks and shocks originating from flare blasts. We study their characteristics in…

We have studied a complex metric radio event which originated in a compact flare, observed with the ARTEMIS-JLS radiospectro-graph on February 12, 2010. The event was associated with a surge observed at 195 and 304 {\AA} and with a coronal…

D-H type II radio bursts are widely thought to be caused by the coronal mass ejections (CMEs). However, it is still unclear where the exact source of the type IIs on the shock surface is. We identify the source regions of the…

Recent studies of interplanetary radio type II bursts and their source locations are reviewed. As these bursts are due to propagating shock waves, driven by coronal mass ejections, they can be followed to near-Earth distances and can be…

The vulnerability of technology on which present society relies demands that a solar event, its time of arrival at Earth, and its degree of geoeffectiveness be promptly forecasted. Motivated by improving predictions of arrival times at…