A5080737607- Solar and Space Plasma Dynamics
- Astro and Planetary Science
- Ionosphere and magnetosphere dynamics
- Solar Radiation and Photovoltaics
- Stellar, planetary, and galactic studies
- Gamma-ray bursts and supernovae
- Astronomical Observations and Instrumentation
- Geomagnetism and Paleomagnetism Studies
- Photovoltaic System Optimization Techniques
- Astronomy and Astrophysical Research
- Radiation Therapy and Dosimetry
- Distributed and Parallel Computing Systems
- Geophysics and Gravity Measurements
- Astrophysics and Cosmic Phenomena
- Earthquake Detection and Analysis
- Laser-Plasma Interactions and Diagnostics
- Particle accelerators and beam dynamics
- Planetary Science and Exploration
- Dark Matter and Cosmic Phenomena
- Solar Thermal and Photovoltaic Systems
- Climate Change Policy and Economics
- Laser-Matter Interactions and Applications
- Global Energy and Sustainability Research
- Spacecraft Design and Technology
- Meteorological Phenomena and Simulations
University of Central Lancashire
2015-2024
Centre National de la Recherche Scientifique
2017
Laboratoire d’études spatiales et d’instrumentation en astrophysique
2017
Université Paris Sciences et Lettres
2017
Université Paris Cité
2017
Met Office
2016
Stanford University
2016
Kavli Institute for Particle Astrophysics and Cosmology
2016
Ruhr University Bochum
2016
University of Manchester
2005-2010
After decades of observations solar energetic particles from space-based observatories, relevant questions on particle injection, transport, and acceleration remain open. To address these scientific topics, accurate measurements the properties in inner heliosphere are needed. In this paper we describe Energetic Particle Detector (EPD), an instrument suite that is part payload aboard Solar Orbiter mission. will approach Sun as close 0.28 au provide extra-ecliptic beyond ∼30° heliographic...
Solar Energetic Particle (SEP) events are interesting from a scientific perspective as they the product of broad set physical processes corona out through extent heliosphere, and provide insight into particle acceleration transport that widely applicable in astrophysics. From operations perspective, SEP pose radiation hazard for aviation, electronics space, human space exploration, particular missions outside Earth's protective magnetosphere including to Moon Mars. Thus, it is critical...
Space weather is a multidisciplinary research area connecting scientists from across heliophysics domains seeking coherent understanding of our space environment that can also serve modern life and society's needs. COSPAR's ISWAT (International Weather Action Teams) "clusters" focus attention on different areas study while ensuring the coupled system broadly addressed via regular communications interactions. The H3 cluster "Radiation in heliosphere" (https://www.iswat-cospar.org/h3) has been...
Drifts are known to play a role in galactic cosmic ray transport within the heliosphere and standard component of propagation models. However, current paradigm Solar Energetic Particle (SEP) holds effects drifts be negligible, they not accounted for most SEP modelling efforts. We present full-orbit test particle simulations Parker spiral interplanetary magnetic field which demonstrate that high energy cause significant asymmetric perpendicular field. Thus many cases assumption aligned SEPs...
Drifts in the Parker spiral interplanetary magnetic field are known to be an important component propagation of galactic cosmic rays, while they thought negligible for Solar Energetic Particles (SEPs). As a result have so far been ignored SEP modelling and data analysis. We examine drift velocities within single particle first-order adiabatic theory, local coordinate system with axis parallel field. show that, presence scattering space, protons at high end energy range experience significant...
Context. On 2020 November 29, the first widespread solar energetic particle (SEP) event of cycle 25 was observed at four widely separated locations in inner (≲1 AU) heliosphere. Relativistic electrons as well protons with energies > 50 MeV were by Solar Orbiter (SolO), Parker Probe, Terrestrial Relations Observatory (STEREO)-A and multiple near-Earth spacecraft. The SEP associated an M4.4 class X-ray flare accompanied a coronal mass ejection extreme ultraviolet (EUV) wave type II radio...
Abstract The Sun is magnetically active and often produces eruptive events on different energetic temporal scales. Until recently, the upper limit of such was unknown believed to be roughly represented by direct instrumental observations. However, two types extreme were discovered recently: solar particle multi-millennial time scale super-flares sun-like stars. Both discoveries imply that might rarely produce events, called (ESE), whose energy could orders magnitude greater than anything we...
Large solar eruptive events, including flares and coronal mass ejections (CMEs), can lead to energetic particle (SEP) events. During these protons are accelerated up several GeV pose numerous space weather risks. These risks include, but not limited to, radiation hazards astronauts disruption satellites electronics. The highest energy SEPs capable of reaching Earth on timescales minutes be detected in ground level enhancements (GLEs). Understanding analyzing events is critical future...
We study test particle trajectories in the vicinity of a three-dimensional (3D) magnetic null point during spine reconnection. Particles are injected into steady-state non-uniform and electric fields derived by Priest & Titov (1996), equations motion numerically integrated. use input parameters typical solar corona, for which reconnection has been suggested as fundamental mechanism responsible acceleration flare events. show that substantial is possible 3D configuration, strong field regime....
In this work, gradual solar energetic particle (SEP) events observed by multiple spacecraft are investigated with model simulations. Based on a numerical solution of the Fokker–Planck focused transport equation including perpendicular diffusion particles, we obtained fluxes SEPs accelerated an interplanetary coronal mass ejection driven shock as it propagates outward through three-dimensional Parker magnetic field. The is treated moving source particles assumed distribution function. We look...
Abstract The capability to predict the parameters of an SEP event such as its onset, peak flux, and duration is critical assessing any potential space weather impact. We present a new flexible modeling system simulating propagation Solar Energetic Particles (SEPs) from locations near Sun given location in heliosphere forecast flux profiles. Particle Radiation SWx (SPARX) uses innovative methodology that allows implementation within operational framework overcome time constraints test...
Solar energetic particles (SEPs) have been observed to easily spread across heliographic longitudes, and the mechanisms responsible for this behavior remain unclear. We use full-orbit simulations of a 10 MeV proton beam in turbulent magnetic field study what extent mean can be described as diffusion early particle event. compare code results solutions Fokker–Planck equation including spatial pitch angle diffusion, one also propagation along random-walking lines. find that meandering lines is...
Context. Current solar energetic particle (SEP) propagation models describe the effects of interplanetary plasma turbulence on SEPs as diffusion, using a Fokker-Planck (FP) equation. However, FP cannot explain observed fast access across average magnetic field to regions that are widely separated in longitude within heliosphere without unrealistically strong cross-field diffusion. Aims. We study whether recently suggested early non-diffusive phase SEP can wide events with realistic transport...
Abstract Solar energetic particles (SEPs), accelerated during solar eruptions, propagate in turbulent wind before being observed with situ instruments. In order to interpret their origin through comparison remote sensing observations of the eruption, we thus must deconvolve transport effects due magnetic fields from SEP observations. Recent research suggests that propagation is guided by meandering fieldlines across mean field. However, lengthening distance SEPs travel, fieldline meandering,...
Abstract The gradient and curvature of the Parker spiral interplanetary magnetic field give rise to guiding-center drifts on cosmic rays (CRs). plasma turbulence present in space is thought suppress drifts; however, extent which they are reduced not clear. We investigate reduction using a new analytic model heliospheric where dominant 2D component has both wavevector vector normal spiral, thus fulfilling main criterion turbulence. use full-orbit test-particle simulations energetic protons...
The parameters of solar energetic particle (SEP) event profiles such as the onset time and peak have been researched extensively to obtain information on acceleration transport SEPs. corotation particle-filled magnetic flux tubes with Sun is generally thought play a minor role in determining intensity profiles. However recent simulations suggested that affects SEP decay phases depends location observer respect active region associated event. We aim determine whether signatures are present...
Solar energetic particles (SEPs) are detected in interplanetary space association with solar flares and coronal mass ejections (CMEs). The magnetic connection between the observing spacecraft active region (AR) source of event is a key parameter determining whether SEPs observed particle event's properties. We investigate an east-west asymmetry detection SEP events present observations discuss its possible link to corotation flux tubes Sun. used published dataset 239 CMEs recorded 2006 2017...
Abstract. In 2000–2001 Ulysses passed from the south to north polar regions of Sun in inner heliosphere, providing a snapshot latitudinal structure cosmic ray modulation and solar energetic particle populations during period near maximum. Observations COSPIN suite charged telescopes show that latitude variations intensity heliosphere are nearly non-existent maximum, whereas small but clear gradients were observed similar phase Ulysses’ orbit 1994–95 minimum. At proton energies above ~10 MeV...
We analyse 9 large solar energetic particle (SEP) events detected by the Ulysses spacecraft at high heliolatitudes during recent maximum polar passes. Properties of time intensity profiles from Ulysses/COSPIN instrument are compared with those measured SOHO/COSTEP and Wind/3DP near Earth. find that onset times to latitude delayed in‐ecliptic values. show parameter which best orders these characteristics is difference in between associated flare spacecraft. presence a shock not necessary for...
Understanding the transport of Solar Energetic Particles (SEPs) from acceleration sites at Sun into interplanetary space and to Earth is an important question for forecasting weather. The Interplanetary Magnetic Field (IMF), with two distinct polarities a complex structure, governs energetic particle drifts. We analyse first time effect wavy Heliospheric Current Sheet (HCS) on propagation SEPs. inject protons close propagate them by integrating fully 3D trajectories within inner heliosphere...
Context: The strong electric fields associated with magnetic reconnection in solar flares are a plausible mechanism to accelerate populations of high energy, non-thermal particles. One such scenario occurs at 3D null point, where global plasma flows give rise currents the spine axis or fan plane. Aims: To understand charged particle energy gain both external drift region and diffusion reconnection. In doing so we evaluate efficiency resistive models for acceleration, find possible...