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Related papers: 3He-rich solar energetic particles: Solar sources

200 papers

We review recent work on 111 Fe-rich impulsive solar energetic ($\sim$ 3 MeV/nuc) particle (SEP) events observed from 1994 to 2013. Strong elemental abundance enhancements scale with A/Q, the ion mass-to-charge ratio, as (A/Q)$^{\alpha}$,…

Solar and Stellar Astrophysics · Physics 2015-10-01 Stephen Kahler , Donald Reames , Edward Cliver

A new mechanism for acceleration and enrichment of 3He during impulsive solar flares is presented. Low-frequency electromagnetic plasma waves excited by the Electron Firehose Instability (EFI) can account for the acceleration of ions up to…

Astrophysics · Physics 2009-11-07 G. Paesold , R. Kallenbach , A. O. Benz

In this note, we consider radio characteristics of three proton flares that caused discrete enhancements of solar energetic particles (SEPs) near Earth. The analysis confirmed that the flux density and frequency spectrum of microwave…

Solar and Stellar Astrophysics · Physics 2018-02-02 I. M. Chertok

This is a study of abundances of the elements He, C, N, O, Ne, Mg, Si, S, Ar, Ca, and Fe in solar energetic particles (SEPs) in the 2 - 15 MeV amu-1 region measured on the Wind spacecraft during 54 large SEP events occurring between…

Solar and Stellar Astrophysics · Physics 2015-06-16 Donald V. Reames

I consider phenomenological changes in the standard solar model with the goal of testing recent claims that the solar neutrino puzzle requires new particle physics. The assumption of a steady-state sun producing the correct luminosity and…

Nuclear Theory · Physics 2008-02-03 W. C. Haxton

Solar Energetic Particles (SEP) are an integral part of the physical processes related with Space Weather. We present a review for the acceleration mechanisms related to the explosive phenomena (flares and/or CMEs) inside the solar corona.…

High Energy Astrophysical Phenomena · Physics 2019-06-12 Loukas Vlahos , Anastasios Anastasiadis , Athanasios Papaioannou , Athanasios Kouloumvakos , Heinz Isliker

The earliest evidence on spatial distributions of solar energetic particles (SEPs) compared events from many different source longitudes on the Sun, but the early Pioneers provided the first evidence of the large areas of equal SEP…

Solar and Stellar Astrophysics · Physics 2023-08-14 Donald V. Reames

Large solar eruptive events, including solar flares and coronal mass ejections (CMEs), can lead to solar energetic particle (SEP) events. During these events, protons are accelerated up to several GeV and pose numerous space weather risks.…

Solar and Stellar Astrophysics · Physics 2023-03-08 Charlotte Waterfall , Silvia Dalla , Osku Raukunen , Daniel Heynderickx , Piers Jiggens , Rami Vainio

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…

Solar and Stellar Astrophysics · Physics 2020-02-27 Donald V. Reames

Solar Energetic Particles (SEPs) are an important component of Space Weather, including radiation hazard to humans and electronic equipment, and the ionisation of the Earth's atmosphere. We review the key observations of SEPs, our current…

Solar and Stellar Astrophysics · Physics 2017-05-23 Karl-Ludwig Klein , Silvia Dalla

To understand the chemical evolution of the Galaxy, we need to understand the contribution of PNe in the 3He abundance. 3He abundances have been detected only in a couple of PNe, their abundances are consistent with the standard models, in…

Astrophysics of Galaxies · Physics 2015-06-15 L. Guzman-Ramirez , J. E. Pineda , A. A. Zijlstra , R. Stancliffe , A. Karakas

Significant progress has been made over the past decades towards unveiling the sources of the most energetic particles in nature, the ultra-high-energy cosmic rays (UHECRs). Despite these advancements, the exact astrophysical sites capable…

High Energy Astrophysical Phenomena · Physics 2025-04-03 Rafael Alves Batista

Context. The remote observations of solar flare ion acceleration are rather limited. There are theoretical predictions for signatures of ion acceleration in EUV line profiles. Previous tests involve observations of flares with no evidence…

Solar and Stellar Astrophysics · Physics 2018-09-19 R. Bucik , A. Fludra , R. Gomez-Herrero , D. E. Innes , B. Kellett , R. Kumar , S. Mackovjak

We report on two 3He-rich solar energetic particle (SEP) events observed by Solar Orbiter (SO) and Parker Solar Probe (PSP) during the April 1 - 4, 2024 conjunction when both spacecraft are within 0.3 AU near their respective perihelion…

Observations relating the characteristics of electrons seen near Earth (SEPs) and those producing flare radiation show that in certain (prompt) events the origin of both population appears to be the flare site, which show strong correlation…

Solar and Stellar Astrophysics · Physics 2016-10-12 Vahe' Petrosian

Solar energetic particles (SEPs), including protons and heavy ions, are believed to be accelerated either by CME shock or by magnetic reconnection. The latter also produces solar flares, in which the white light flares (WLFs) are among the…

Solar and Stellar Astrophysics · Physics 2018-01-16 Nengyi Huang , Yan Xu , Haimin Wang

The magnetic field of the Sun drives a wide range of eruptive phenomena, from small-scale nanoflares to large flares and coronal mass ejections (CMEs). While direct observations of solar activity cover only the past few decades, indirect…

Solar and Stellar Astrophysics · Physics 2026-02-12 Valeriy Vasilyev , Natalie Krivova , Ilya Usoskin

Solar energetic particles (SEPs) in the energy range 10s KeV/nucleon-100s MeV/nucleon originate from Sun. Their high flux near Earth may damage the space borne electronics and generate secondary radiations harmful for the life on Earth and…

Plasma Physics · Physics 2025-07-18 Neeraj Jain , Jörg Büchner , Miroslav Bárta , Radoslav Bučík

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 and Stellar Astrophysics · Physics 2015-06-12 Sophie Masson , Spiro K. Antiochos , C. Rick DeVore

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…