Coronal Mass Ejection (CME)

Are Solar Energetic Particle Events and Type II Bursts Associated with Fast and Narrow Coronal Mass Ejections?
by S. W. Kahler et al.*

2019-12-10

Gradual solar energetic (E > 10 MeV) particle (SEP) events, lasting several days, are produced in coronal/interplanetary shocks driven by fast (VCME ≥ 900 kms−1) coronal mass ejections (CMEs) associated with type II radio bursts.  The basic paradigm is that CMEs with VCME > Vf, the plasma fast-mode speed, drive shocks that can accelerate seed particles to the high energies observed as SEP events in space as well as electrons […]

Imaging spectroscopy of fiber bursts
by C. Alissandrakis*

2019-10-15

Fibers are short metric/decimetric bursts with a drift rate between type II and type III bursts, usually appearing in groups embedded in type IV continua. In most cases they show both absorption and emission ridges, the absorption having a slightly lower frequency than the emission. They are, most probably, manifestations of whistler-Langmuir wave interaction and they travel upwards along post flare loops (Kuijpers 1975). In a recent work (Bouratzis et […]

3D reconstruction of CME-driven shock-streamer interaction as a coronal magnetic field diagnostics
by S. Mancuso et al.*

2019-06-04

Coronal Mass Ejections (CMEs) expelled from the Sun can drive shocks that accelerate electrons which, in turn, produce electrostatic oscillations called Langmuir waves. These waves are then converted into escaping e.m. radiation, known as type II solar radio bursts, emitted near the fundamental and/or harmonic of the local electron plasma frequency. As shocks propagate outward from the Sun to regions of lower plasma density, type IIs appear in dynamic spectra […]

Variable Emission Mechanism of a Type IV Radio Burst
by D. Morosan et al.*

2019-04-23

Coronal mass ejections (CMEs) are sometimes accompanied by continuum emission at decimetric and metric wavelengths, called Type IV radio bursts. Of particular interest to determining CME properties are moving Type IV radio bursts, which are broadband radio sources moving outwards from the Sun. First studies suggested that moving Type IV bursts are emitted by synchrotron or gyro-synchrotron emitting electrons that are trapped inside CME loops (Dulk 1973). However, since their […]

Source Imaging of a Moving Type-IV Solar Radio Burst and its Role in Tracking Coronal Mass Ejection From the Inner to the Outer Corona
by Y. Chen et al.

2019-02-26

T-IV solar radio bursts are wideband continuum observed with dynamic spectrographs at metric to decametric wavelengths. They can be classified into static and moving ones, according to whether the sources remain basically static or move outward. The static ones are related to solar flares with frequencies extending up to GHz, while the moving ones (T-IVms) are related to coronal mass ejections (CMEs) with frequencies sometimes shifting to tens of MHz. […]

Coronal Mass Ejection-driven Type II solar radio burst structure with LOFAR and radio-wave scattering
by Nicolina Chrysaphi et al.*

2019-01-29

Coronal Mass Ejections (CMEs) are often viewed as the major drivers of space weather disturbances in the Sun-Earth system. Shocks driven by CMEs can excite radio emissions characterised by a slow frequency drift across dynamic spectra. These radio emissions are known as Type II solar radio bursts and can consist of two bands with a frequency ratio of 1:2. Each of these bands can split into two thinner sub-bands, a […]

Coronal mass ejections associated to a super-active region
by H. Cremades et al.*

2018-12-18

During its transit through central meridian, and along four consecutive days, from 13 to 16 February 2011, NOAA active region (AR) 11158 generated coronal mass ejections (CMEs) in association with waves observed in the extreme ultraviolet (EUV) low corona, and even with a Moreton wave. On those dates, the spacecraft of the STEREO mission were located in quadrature with SOHO and SDO, enabling the exceptional observation of this series of […]

Shock location and CME 3-D reconstruction of a solar type II radio burst with LOFAR
by P. Zucca et al.*

2018-10-30

Type II radio bursts are the result of shocks in the solar atmosphere and they can be observed ranging from sub-metric to kilometric wavelengths (~400 MHz to ~0.4 MHz). Coronal mass ejections initiate most of the metric type II (m-type II) bursts. The region of a CME responsible for driving the shock might be different for each event and has not yet been comprehensively identified. Multiple scenarios have been suggested, […]

1 2 3 4 5 6

CESRA webpage © 2024 | Made using WordPress Theme by MH Themes