*Context.* The shape of the pitch-angle distribution (PAD) of solar energetic particles (SEPs) can be used to infer information about their source and interplanetary transport. In modeling and observational studies of SEP events, these PADs are …
*Context.* Solar Orbiter strives to unveil how the Sun controls and shapes the heliosphere and fills it with energetic particle radiation. To this end, its Energetic Particle Detector (EPD) has now been in operation, providing excellent data, for …
*Context.* Sheath regions ahead of coronal mass ejections (CMEs) are large-scale heliospheric structures that form gradually with CME expansion and propagation from the Sun. Turbulent and compressed sheaths could contribute to the acceleration of …
*Context.* On 2020 November 29, the first widespread solar energetic particle (SEP) event of solar cycle 25 was observed at four widely separated locations in the inner (≲1 AU) heliosphere. Relativistic electrons as well as protons with energies 50 …
*Aims.* We aim to constrain the acceleration, injection, and transport processes of flare-accelerated energetic electrons by comparing their characteristics at the Sun with those injected into interplanetary space. *Methods.* We have identified 17 …
*Context.* Late on 2013 August 19, STEREO-A, STEREO-B, MESSENGER, Mars Odyssey, and the L1 spacecraft, spanning a longitudinal range of 222° in the ecliptic plane, observed an energetic particle flux increase. The widespread solar energetic particle …