Related papers: Compression Acceleration of Protons and Heavier Io…
During near-Sun crossings of the heliospheric current sheet (HCS), Parker Solar Probe (PSP) observed populations of high-energy protons and heavier ions indicating possible energization by magnetic reconnection up to 10s -- 100s keV…
We report observations of direct evidence of energetic protons being accelerated above ~400 keV within the reconnection exhaust of a heliospheric current sheet (HCS) crossing by NASA's Parker Solar Probe (PSP) at a distance of ~16.25 solar…
We present observations of >10-100 keV/nucleon suprathermal (ST) H, He, O, and Fe ions associated with crossings of the heliospheric current sheet (HCS) at radial distances <0.1 au from the Sun. Our key findings are: 1) very few heavy ions…
The acceleration of protons and electrons in a reconnecting current sheet (RCS) is simulated with a particle-in-cell (PIC) 2D3V code for the proton-to-electron mass ratio of 100. The electro-magnetic configuration forming the RCS…
We study the acceleration of electrons and protons interacting with localized, multiple, small-scale dissipation regions inside an evolving, turbulent active region. The dissipation regions are Unstable Current Sheets (UCS), and in their…
We present the results of 3D particle-in-cell (PIC) simulations that explore relativistic magnetic reconnection in pair plasma with strong synchrotron cooling and a small mass fraction of non-radiating ions. Our results demonstrate that the…
Pulsars have been identified as good candidates for the acceleration of cosmic rays, up to ultra-high energies. However, a precise description of the acceleration processes at play is still to be established. Using 2D particle-in-cell…
Proton acceleration by high-intensity laser pulses from ultra-thin foils for hadron therapy is discussed. With the improvement of the laser intensity contrast ratio to 10-11 achieved on Hercules laser at the University of Michigan, it…
We demonstrate in this research the quasi-monoenergetic electron and proton acceleration through three dimensional particle-in-cell simulations of short petawatt circular polarized laser pulse interactions with near critical density…
The acceleration of ions from ultra-thin foils has been investigated using 250 TW, sub-ps laser pulses, focused on target at intensities up to $3\times10^{20} \Wcm2$. The ion spectra show the appearance of narrow band features for proton…
Clusters of galaxies are believed to be capable to accelerate protons at accretion shocks to energies exceeding 10^18 eV. At these energies, the losses caused by interactions of cosmic rays with photons of the Cosmic Microwave Background…
Solar Energetic Particles (SEPs), a major component of space weather, propagate through the interplanetary medium strongly guided by the Interplanetary Magnetic Field (IMF). In this work, we analyse the implications a flat Heliospheric…
We analyze measured proton and electron temperatures in the high-speed solar wind in order to calculate the separate rates of heat deposition for protons and electrons. When comparing with other regions of the heliosphere, the fast solar…
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…
In solar flares and other astrophysical systems, a major challenge for solving particle acceleration problem associated with magnetic reconnection is the enormous scale separation between kinetic scales and observed reconnection scale.…
Stochastic acceleration of electrons and protons by waves propagating parallel to the large scale magnetic fields of magnetized plasmas is studied with emphasis on the feasibility of accelerating particles from a thermal background to…
Increases of ion fluxes in the keV-MeV range are sometimes observed near the heliospheric current sheet (HCS) during periods when other sources are absent. These resemble solar energetic particle (SEP) events, but the events are weaker and…
An investigation into the acceleration of protons by scattering off relativistic Alfv\'{e}n waves in the accretion column of Hercules X-1 is presented. The mechanism is shown to achieve mean particle energies of 30~TeV under very reasonable…
Understanding the transport of Solar Energetic Particles (SEPs) from acceleration sites at the Sun into interplanetary space and to the Earth is an important question for forecasting space weather. The Interplanetary Magnetic Field (IMF),…
We report the results of 1D particle-in-cell simulations of ultrarelativistic shock waves in proton-electron-positron plasmas. We consider magnetized shock waves, in which the upstream medium carries a large scale magnetic field, directed…