Related papers: Enhancing Explainability in Solar Energetic Partic…
The Sun is already in the declining phase of cycle 24, but the paucity of high-energy solar energetic particle (SEP) events continues with only two ground level enhancement (GLE) events as of March 31, 2015. In an attempt to understand…
The nature of particle acceleration at the Sun, whether through flare reconnection processes or through shocks driven by coronal mass ejections (CMEs), is still under scrutiny despite decades of research. The measured properties of solar…
The excess temperature of the solar corona over the photosphere poses a challenge. Multiple energetic events contribute to maintaining the corona at such high temperatures. The energy released in different events can vary across several…
The solar wind is a dynamic plasma outflow that shapes heliospheric conditions and drives space weather. Identifying its large-scale phenomena is crucial, yet the increasing volume of high-cadence Parker Solar Probe (PSP) observations poses…
Large solar eruptions are often associated with long-duration gamma-ray emission extending well above 100 MeV. While this phenomenon is known to be caused by high-energy ions interacting with the solar atmosphere, the underlying dominant…
We discuss possible mechanisms of acceleration of particles in solar flares and show that turbulence plays an important role in all the mechanism. It is also argued that stochastic particle acceleration by turbulent plasma waves is the most…
This paper investigates the onset time of Solar Energetic Particle (SEP) events with numerical simulations, and analyses the accuracy of the Velocity Dispersion Analysis (VDA) method. Using a 3-dimensional focused transport model, we…
Recent detection of superflares on solar-type stars by Kepler mission raised a possibility that they can be associated with energetic coronal mass ejections (CMEs) and energetic particle events (SEPs). These space weather events can impact…
Coronal mass ejections (CMEs) drive powerful shocks and thereby accelerate solar energetic particles (SEPs) as they propagate from the corona into interplanetary space. Here we present the processes of three-stage particle acceleration by a…
We have statistically analyzed a set of 115 low frequency (Deca- Hectometer wavelengths range) type II and type III bursts associated with major Solar Energetic Particle (SEP: Ep > 10 MeV) events and their solar causes such as solar flares…
Forecasting solar energetic particles (SEPs), and identifying flare/CMEs from active regions (ARs) that will produce SEP events in advance is extremely challenging. We investigate the magnetic field environment of AR 12673, including the…
The Solar Accumulated and Peak Proton and Heavy Ion Radiation Environment (SAPPHIRE) model provides environment specification outputs for all aspects of the Solar Energetic Particle (SEP) environment. The model is based upon a thoroughly…
Shock waves driven by fast and wide coronal mass ejections (CMEs) are highly efficient particle accelerators involved in the production of solar energetic particle (SEP) events. The gradual SEP event measured by STEREO-A and B on October…
Proceeding from close association between solar eruptions, flares, shock waves, and CMEs, we analyze relations between bursts at 35 GHz recorded with the Nobeyama Radio Polarimeters during 1990-2012, on the one hand, and solar energetic…
We address the problem of how particles that are accelerated by solar flares can escape promptly into the heliosphere, on time scales of an hour or less. Impulsive solar energetic particles (SEP) bursts are generally observed in association…
Solar flares and coronal mass ejections are interrelated phenomena that together are known as solar eruptive events. These are the main drivers of space weather and understanding their origins is a primary goal of Heliophysics. In this…
We revisited assessments of the occurrence probability distribution of large events in solar energetic particles (SEP), based on measurements of cosmogenic radionuclides in lunar rocks. We present a combined cumulative occurrence…
We present simulation results of a gradual solar energetic particle (SEP) event detected on 2021 October 9 by multiple spacecraft, including BepiColombo (Bepi) and near-Earth spacecraft such as the Advanced Composition Explorer (ACE). A…
The solar eruption on 2012 January 27 resulted in a wide-spread solar energetic particle (SEP) event observed by STEREO A and the near-Earth spacecraft (separated by 108\degree). The event was accompanied by an X-class flare,…
Geomagnetic field variations during five major Solar Energetic Particle (SEP) events of solar cycle 23 have been investigated in the present study. The SEP events of 01 oct 2001, 04 Nov 2001, 21 Apr 2002 and 14 May 2005 have been selected…