Search Publications
Radial evolution of interplanetary coronal mass ejection-associated particle acceleration observed by Solar Orbiter and ACE
Li, Gang; Kouloumvakos, Athanasios; Wimmer-Schweingruber, Robert F. +5 more
On 2022 March 10 a coronal mass ejection erupted from the Sun, resulting in Solar Orbiter observations at 0.45 au of both dispersive solar energetic particles arriving prior to the interplanetary coronal mass ejection (ICME) and locally accelerated particles near the ICME-associated shock structure as it passed the spacecraft on 2022 March 11. Thi…
Solar energetic particles injected inside and outside a magnetic cloud: The widespread solar energetic particle event on 2022 January 20
Palmerio, E.; Jebaraj, I. C.; Laitinen, T. +22 more
Context. On 2022 January 20, the Energetic Particle Detector (EPD) on board Solar Orbiter measured a solar energetic particle (SEP) event showing unusual first arriving particles from the anti-Sun direction. Near-Earth spacecraft separated by 17° in longitude to the west of Solar Orbiter measured classic anti-sunward-directed fluxes. STEREO-A and …
SIP-IFVM: Efficient time-accurate magnetohydrodynamic model of the corona and coronal mass ejections
Poedts, S.; Guo, Y.; Guo, J. H. +7 more
Context. Coronal mass ejections (CMEs) are one of the main drivers of space weather. However, robust and efficient numerical modelling applications of the initial stages of CME propagation and evolution process in the sub-Alfvénic corona are still lacking. Aims. Magnetohydrodynamic (MHD) solar coronal models are critical in the Sun-to-Earth model …
Determining the acceleration regions of in situ electrons using remote radio and X-ray observations
Jebaraj, I. C.; Vainio, R.; Kilpua, E. K. J. +13 more
Context. Solar energetic particles in the heliosphere are produced by flaring processes on the Sun or by shocks driven by coronal mass ejections. These particles are regularly detected remotely as electromagnetic radiation (X-rays or radio emission), which they generate through various processes, or in situ by spacecraft monitoring the Sun and the…
Radio dimming associated with filament eruptions in the meter and decimeter wavebands
Feng, Li; Tian, Hui; Madjarska, Maria S. +12 more
Filament eruptions are considered to be a common phenomenon on the Sun and other stars, yet they are rarely directly imaged in the meter and decimeter wavebands. Using imaging data from the DAocheng solar Radio Telescope (DART) in the 150‑450 MHz frequency range, we present two eruptive filaments that manifest as radio dimmings (i.e., emission dep…
A new method for determining the onset times of solar energetic particles and their uncertainties: Poisson-CUSUM bootstrap hybrid method
Gutiérrez, C. P.; Vainio, R.; Dresing, N. +2 more
Context. Solar energetic particle (SEP) events are a type of space weather phenomena in which highly energetic charged particles are released from the Sun into interplanetary space by violent and eruptive phenomena, such as solar flares and coronal mass ejections. In order to assess the origin of SEPs, an accurate timing of their arrival at spacec…
Estimating uncertainties in the back-mapping of the fast solar wind
Dolla, L.; Keppens, R.; Koukras, A.
Context. Although the most likely source regions of fast solar wind relate to coronal holes, the exact acceleration mechanism that drives the fast solar wind is still not fully understood. An important approach that can improve our understanding involves the combination of remote sensing and in situ measurements, often referred to as linkage analy…
Flaring together: A preferred angular separation between sympathetic flares on the Sun
Strugarek, A.; Charbonneau, P.; Guité, L. -S.
Context. Sympathetic solar flares are eruptions that occur nearby in space and time, driven by an apparent interaction between the active regions in which they are triggered. Their statistical existence on the Sun has yet to be firmly established. Aims. The main goal of this paper is to identify a statistical signature of sympathetic flares, chara…
Multi-spacecraft observations of the decay phase of solar energetic particle events
Laitinen, T.; Wimmer-Schweingruber, R. F.; Dalla, S. +3 more
Context. The parameters of solar energetic particle (SEP) event profiles such as the onset time and peak time have been researched extensively to obtain information on the acceleration and transport of SEPs. The corotation of particle-filled magnetic flux tubes with the Sun is generally thought to play a minor role in determining intensity profile…
Stellar flare morphology with TESS across the main sequence
Kriskovics, L.; Pál, A.; Görgei, A. +5 more
Context. Stellar flares are abundant in space photometric light curves. As they are now available in large enough numbers, the statistical study of their overall temporal morphology is timely. Aims. We use light curves from the Transiting Exoplanet Survey Satellite (TESS) to study the shapes of stellar flares beyond a simple parameterization by du…