Related papers: Suprathermal electron acceleration by a quasi-perp…
Solar flare electron acceleration is an efficient process, but its properties (mechanism, location) are not well constrained. Via hard X-ray (HXR) emission, we routinely observe energetic electrons at the Sun, and sometimes we detect…
General relativistic magnetohydrodynamic (GRMHD) simulations of black hole tilted disks -- where the angular momentum of the accretion flow at large distances is misaligned with respect to the black hole spin -- commonly display standing…
We reexamine stochastic Fermi acceleration (STFA) in the low energy (Newtonian) regime in the context of solar flares. The particle energization rate depends a dispersive term and a coherent gain term. The energy dependence of pitch angle…
Delayed radio flares of optical tidal disruption events (TDEs) indicate the existence of non-relativistic outflows accompanying TDEs. The interaction of TDE outflows with the surrounding circumnuclear medium creates quasi-perpendicular…
There have been several ideas proposed to explain how the Sun's corona is heated and how the solar wind is accelerated. Some models assume that open magnetic field lines are heated by Alfven waves driven by photospheric motions and…
Collisionless shock waves, ubiquitous in the universe, are crucial for particle acceleration in various astrophysical systems. Currently, the heliosphere is the only natural environment available for their in situ study. In this work, we…
Low sonic Mach number shocks form in the intracluster medium (ICM) during the formation of the large-scale structure of the universe. Nonthermal cosmic-ray (CR) protons are expected to be accelerated via diffusive shock acceleration (DSA)…
Solar flares are explosive releases of magnetic energy stored in the solar corona, driven by magnetic reconnection. These events accelerate electrons, generating hard X-ray emissions and often display Quasi Periodic Pulsations (QPPs) across…
Aims. We perform a statistical study of the relations between the properties of solar energetic electron (SEE) events measured by the MESSENGER mission from 2010 to 2015 and the parameters of the respective parent solar activity phenomena…
The analysis of Balmer-dominated optical spectra from non-radiative (adiabatic) SNRs has shown that the ratio of the electron to proton temperature temperature at the blast wave is close to unity at v_s <= 400 km/s, but declines sharply…
As solar coronal mass ejections (CMEs) propagate through the heliosphere, they expend energy in heating protons to compensate for the cooling that occurs due to expansion. CME propagation models usually treat energy dissipation implicitly…
We consider a phenomenological model for the thermal leakage injection in the diffusive shock acceleration (DSA) process, in which suprathermal protons and electrons near the shock transition zone are assumed to have the so-called…
Based on the drift-kinetic theory, we develop a model for particle acceleration and transport in solar flares. The model describes the evolution of the particle distribution function by means of a numerical simulation of the drift-kinetic…
We calculate the interplanetary magnetic field path lengths traveled by electrons in solar electron events detected by the WIND 3DP instrument from $1994$ to $2016$. The velocity dispersion analysis method is applied for electrons at…
The leading explanation for the origin of galactic cosmic rays is particle acceleration at the shocks surrounding young supernova remnants (SNRs), although crucial aspects of the acceleration process are unclear. The similar collisionless…
Solar flares are efficient particle accelerators with a large fraction of released magnetic energy (10-50%) converted into energetic particles such as hard X-ray producing electrons. This energy transfer process is not well constrained,…
Scattering, during interplanetary transport in large, "gradual" solar energetic-particle (SEP) events, can cause element abundance enhancements or suppressions that depend upon the mass-to-charge ratio A/Q of the ions as an increasing…
A popular scenario for electron acceleration in solar flares is transit-time damping of low-frequency MHD waves excited by reconnection and its outflows. The scenario requires several processes in sequence to yield energetic electrons of…
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…
We use 2.5-D electromagnetic particle-in-cell simulation code to investigate the acceleration of electrons in solar coronal holes through the interaction of Alfv\'en waves with an interplume region. The interplume is modeled by a cavity…