Related papers: Long-lived energetic particle source regions on th…
On 2019 May 6, the Lunar Lander Neutron & Dosimetry (LND) Experiment on board the Chang'E-4 on the far-side of the Moon detected its first small solar energetic particle (SEP) event with proton energies up to 21MeV. Combined proton energy…
Solar Energetic Particles (SEPs) are charged particles accelerated within the solar atmosphere or the interplanetary space by explosive phenomena such as solar flares or Coronal Mass Ejections (CMEs). Once injected into the interplanetary…
Large gradual solar energetic particle (SEP) events can pose a radiation risk to crewed spaceflight and a significant threat to near-Earth satellites however, the origin of the SEP seed particle population, how these particles are released,…
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…
During mid-May 2024, active region (AR) 13664 produced a series of M- and X-class flares along with several coronal mass ejections (CMEs) that resulted in exceptionally strong aurora at Earth. This study presents in-situ solar energetic…
Multi-spacecraft observations of solar energetic particle (SEP) events not only enable a deeper understanding and development of particle acceleration and transport theories, but also provide important constraints for model validation…
Metric type II solar radio bursts and solar energetic particles (SEPs) are both associated with shock fronts driven by coronal mass ejections (CMEs) in the solar corona. Recent studies of ground level enhancements (GLEs), regular large…
On 13 March 2023, when the Parker Solar Probe was situated on the far side of the Sun as seen from Earth, a large solar eruption took place creating a strong solar energetic particle (SEP) event observed by multiple spacecraft (S/C). The…
We present a detailed investigation of the shock properties associated with solar energetic particle (SEP) events that exhibit a concave (``nose-like'') shape in their energy spectrogram, characterized by inverse velocity arrival (IVA) of…
We report that the number of > 500 MeV protons (Ng) inferred from sustained gamma ray emission (SGRE) from the Sun is significantly correlated with that of protons propagating into space (NSEP) as solar energetic particles (SEPs). Under the…
Solar energetic particles (SEPs) accelerated from shocks driven by coronal mass ejections (CMEs) are one of the major causes of geomagnetic storms on Earth. Therefore, it is necessary to predict the occurrence and intensity of such…
We study selected properties of Solar Energetic Particle (SEP) events as inferred from their associated radio emissions. We used a catalogue of 115 SEP events that consists of entries of proton intensity enhancements at one AU, with…
In solar energetic particle (SEP) events, the physical processes of both shock acceleration and scattering during transport can cause energy-spectral indices to be correlated with enhancement or suppression of element abundances versus…
We have studied the dynamic proton spectra for the two solar energetic particle (SEP) events on 2000 July 14 (hereafter GLE59) and 2005 January 20 (hereafter GLE69). The source locations of GLE59 and GLE69 are N22W07 and N12W58…
Based upon recent evidence from abundance patterns of chemical elements in solar energetic particles (SEPs), and, ironically, the belated inclusion of H and He, we can distinguish four basic SEP populations: (1) SEP1 - pure "impulsive" SEPs…
We study the large solar energetic particle (SEP) events that were detected by GOES in the $>$ 10 MeV energy channel during December 2006 to March 2014. We derive and compare solar particle release (SPR) times for the 0.25--10.4 MeV…
Studies of patterns of abundance enhancements of elements, relative to solar-coronal abundances, in large solar energetic-particle (SEP) events, and of their power-law dependence on the mass-to-charge ratio A/Q of the ions, have been used…
The author has been fortunate to observe and participate in the rise of the field of solar energetic particles (SEPs), from the early abundance studies, to the contemporary paradigm of shock acceleration in large SEP events, and element…
The Sun drives a supersonic wind which inflates a giant plasma bubble in our very local interstellar neighborhood, the heliosphere. It is bathed in an extremely variable background of energetic ions and electrons which originate from a…
We revisit the full variety of observed temporal and spatial distributions of energetic solar protons in "gradual" solar energetic-particle (SEP) events resulting from the spatial variations in the shock waves that accelerate them.…