Related papers: Magnetic Field Strength in the Upper Solar Corona …
For all involved in astronomy, the importance of monitoring and determining astrophysical magnetic field strengths is clear. It is also a well-known fact that the corona magnetic fields play an important part in the origin of solar flares…
Spectroscopic observations of a solar limb flare recorded by SUMER on SOHO reveal, for the first time, hot fast magnetic reconnection outflows in the corona. As the reconnection site rises across the SUMER spectrometer slit, significant…
This study based on longitudinal Zeeman effect magnetograms and spectral line scans investigates the dependence of solar surface magnetic fields on the spectral line used and the way the line is sampled in order to estimate the magnetic…
In this work, we focus on the analysis of a CME-driven shock observed by SOHO/LASCO. We show that white-light coronagraphic images can be employed to estimate the compression ratio X = rho_d / rho_u all along the front of CME-driven shocks.…
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 present results from a set of numerical simulations aimed at exploring the mechanism of coronal mass ejection (CME) suppression in active stars by an overlying large-scale magnetic field. We use a state-of-the-art 3D magnetohydrodynamic…
Fast coronal mass ejections (CMEs) can drive shock waves capable of accelerating electrons to high energies. These shock-accelerated electrons act as sources of electromagnetic radiation, often in the form of solar radio bursts. Recent…
Aims. The magnetic field of coronal mass ejections (CMEs) determines their structure, evolution, and energetics, as well as their geoeffectiveness. However, we currently lack routine diagnostics of the near-Sun CME magnetic field, which is…
Estimating the magnetic field strength in the solar corona is crucial for understanding different physical processes happening over diverse spatio-temporal scales. However, the high temperatures and low density of the solar corona make this…
Analysis of Mark 4 and LASCO C2, C3 coronagraph data shows that, at the distance $R \leq 6$ R$_\odot$ from the center of the Sun, the thickness of a CME-generated shock-wave front ($\delta_F$) may be of order of the proton mean free path.…
The magnetic field in the Sun's corona stores energy that can be released to heat the coronal plasma and drive solar eruptions. Measurements of the global coronal magnetic field have been limited to a few snapshots. We present observations…
Fast coronal mass ejections (CMEs) generate standing or bow shocks as they propagate through the corona and solar wind. Although CME shocks have previously been detected indirectly via their emission at radio frequencies, direct imaging has…
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 (CME) that occurred in…
Measurements of the stellar coronal magnetic field are of great importance in understanding the stellar magnetic activity, yet the measurements have been extremely difficult. Recent studies proposed a new method of magnetic field…
Analysis of SOHO/LASCO C3 data reveals a discontinuity, interpreted as a shock wave, in plasma density radial profiles in a restricted region ahead of each of ten selected coronal mass ejections (CME) along their travel directions. In…
Coronal mass ejections (CMEs) are thought to drive collisionless shocks in the solar corona, which in turn have been shown capable of accelerating solar energetic particles (SEPs) in minutes. It has been notoriously difficult to extract…
Aims: We investigate whether solar coronal mass ejections are driven mainly by coupling to the ambient solar wind or through the release of internal magnetic energy. Methods: We examine the energetics of 39 flux-rope like coronal mass…
Coronal mass ejections (CMEs) may disturb the solar wind either by overtaking it, or by expanding into it, or both. CMEs whose front moves faster in the solar wind frame than the fast magnetosonic speed, drive shocks. Such shocks are…
Aims. We aim to infer information about the magnetic field in the low solar corona from coronal rain clumps using high-resolution spectropolarimetric observations in the Ca ii 8542 A line obtained with the Swedish 1-m Solar Telescope.…
Measurements of the magnetic field in the stellar coronae are extremely difficult. Recently, it was proposed that the magnetic-field-induced transition (MIT) of the Fe X 257 {\AA} line can be used to measure the coronal magnetic field of…