Related papers: A coronal seismological study with streamer waves
Solar energetic particles acceleration by a shock wave accompanying a coronal mass ejection (CME) is studied. The description of the accelerated particle spectrum evolution is based on the numerical calculation of the diffusive transport…
The plasma density enhancements recently observed by the Large-Angle Spectrometric Coronagraph (LASCO) instrument onboard the Solar and Heliospheric Observatory (SOHO) spacecraft have sparked considerable interest. In our previous…
Past observations show that solar wind (SW) acceleration occurs inside the sub-Alfvenic region, reaching the local Alfven speed at typical distances ~ 10 - 20 Rs (solar radii). Recently, Parker Solar Probe (PSP) traversed regions of…
We report here on the determination of plasma physical parameters across a shock driven by a Coronal Mass Ejection using White Light (WL) coronagraphic images and Radio Dynamic Spectra (RDS). The event analyzed here is the spectacular…
Recurrent, arc-shaped intensity disturbances were detected by EUV channels in an active region. The fronts were observed to propagate along a coronal loop bundle rooted in a small area within a sunspot umbra. Previous works have linked…
The release of density structures at the tip of the coronal helmet streamers, likely as a consequence of magnetic reconnection, contributes to the mass flux of the slow solar wind. In situ measurements in the vicinity of the heliospheric…
The origin of the heliospheric magnetic flux on the Sun, and hence the origin of the solar wind, is a topic of hot debate.While the prevailing view is that the solar wind originates from outside coronal streamer helmets, there also exists…
Broadly, solar wind source regions can be classified by their magnetic topology as intermittently and continuously open to the heliosphere. Early models of solar wind acceleration do not account for the fastest, non-transient solar wind…
Determining the mechanisms responsible for the heating of the coronal plasma and maintaining and accelerating the solar wind are long standing goals in solar physics. There is a clear need to constrain the energy, mass and momentum flux…
The slow solar wind belt in the quiet corona, observed with the Metis coronagraph on board Solar Orbiter on May 15, 2020, during the activity minimum of the cycle 24, in a field of view extending from 3.8 $R_\odot$ to 7.0 $R_\odot$, is…
We report the properties of electron distributions and turbulence during a Coronal Mass Ejection (CME) in April 2023 observed by Magnetospheric Multiscale (MMS). The CME exhibits a clear sheath and magnetic cloud (MC), and within the MC,…
Cool giant and supergiant stars generally present low velocity winds with high mass loss rates. Several models have been proposed to explain the acceleration process of these winds. Although dust is known to be present in these objects, the…
The existence of shocks driven by Coronal Mass Ejections (CMEs) has always been assumed based on the superalfvenic speeds for some of these events and on indirect evidence such as radio bursts and distant streamer deflections. However, the…
At the site of their origin, solar meterwave radio bursts contain pristine information about the local coronal magnetic field and plasma parameters. On its way through the turbulent corona, this radiation gets substantially modified due to…
Both remote-sensing measurements using the interplanetary scintillation (IPS) technique and in situ measurements by the Ulysses spacecraft show a bimodal structure for the solar wind at solar minimum conditions. At present what makes the…
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…
We report the first experimental detection of a reflected Alfv\'en wave from an Alfv\'en-speed gradient under conditions similar to those in coronal holes. The experiments were conducted in the Large Plasma Device at the University of…
We use images of high spatial, spectral and temporal resolution, obtained using both ground- and space-based instrumentation, to investigate the coupling between wave phenomena observed at numerous heights in the solar atmosphere. Intensity…
We investigate the formation of the H I Lyman-alpha and Lyman-beta lines in an equatorial coronal streamer. Particular attention is paid to frequency redistribution for the scattering of the incident radiation. The properties of the…
The impulsive phase of a solar flare marks the epoch of rapid conversion of energy stored in the pre-flare coronal magnetic field. Hard X-ray observations imply that a substantial fraction of flare energy released during the impulsive phase…