Related papers: Non-equilibrium ionization effects on solar EUV an…
Transit observations in the helium triplet around 10830 Angstrom are a successful tool to study exoplanetary atmospheres and their mass loss. Forming those lines requires ionisation and recombination of helium in the exoplanetary…
We present 1X2V continuum Vlasov-Maxwell simulations of interpenetrating plasma beams with mobile ions. While the early-time evolution is similar to the stationary-ion case, the late-time dynamics are dominated by the ion-Weibel…
The aim of this work is to improve the modelling of ion populations in higher density, lower temperature astrophysical plasmas, of the type commonly found in lower solar and stellar atmospheres. Ion population models for these regions…
The dynamics triggered by the impact of an ion onto a solid surface has been explored mainly by theoretical modeling or computer simulation to date. Results indicate that the microscopic non-equilibrium relaxation processes triggered by the…
For warm or hot and dense plasma, ionization potential depression plays a crucial role in determining the ionization balance and understanding the resulting microscopic plasma properties. However, the applicability of the widely used IPD…
We present radio and X-ray observations of an impulsive solar flare that was moderately intense in microwaves, yet showed very meager EUV and X-ray emission. The flare occurred on 2001 Oct 24 and was well-observed at radio wavelengths by…
Every observation of astrophysical objects involving a spectrum requires atomic data for the interpretation of line fluxes, line ratios and ionization state of the emitting plasma. One of the processes which determines it is collisional…
In the present work we use a deep-exposure spectrum taken by the SUMER spectrometer in a polar coronal hole in 1996 to measure the ion temperatures of a large number of ions at many different heights above the limb between 0.03 and 0.17…
This paper describes the effects of electronic nonequilibrium in a simulation of ultrafast laser irradiation of materials. The simulation scheme based on tight-binding molecular dynamics, in which the electronic populations are traced with…
The hydrogen plasma is studied at temperatures T ~ 10^4 - 10^6 K using the free energy minimization method. A simple analytic free energy model is proposed which is accurate at densities up to 1 g/cc and yields convergent internal partition…
While ion heating by elastic electron-ion collisions may be neglected for a description of the evolution of freely expanding ultracold neutral plasmas, the situation is different in scenarios where the ions are laser-cooled during the…
The effects of radiation on the structure of shocks in a fully-ionized plasma are investigated by solving the steady-state fluid equations for ions, electrons, and radiation. The electrons and ions are assumed to have the same bulk velocity…
We present results of semi-analytic calculations which show clear evidence for changes in the non-equilibrium ionization behind a supernova remnant forward shock undergoing efficient diffusive shock acceleration (DSA). The efficient…
Transition region (TR) spectra typically show the Si IV 1402.8 A line to be enhanced by a factor of 5 or more compared to the neighboring O IV 1401.2 A, contrary to predictions of ionization equilibrium models and the Maxwellian…
X-ray and EUV solar flare emission cause increases in the Earth's dayside ionospheric electron density. While the response of the lower ionosphere to X-rays is well studied, the delay between EUV flare emission and the response of the…
Atomic data and plasma models play a crucial role in the diagnosis and interpretation of astrophysical spectra, thus influencing our understanding of the universe. In this investigation we present a systematic comparison of the leading…
The dynamical evolution of hot optically thin plasmas in the ISM crucially depends on the heating and cooling processes. It is essential to realize that all physical processes that contribute operate on different time scales. In particular…
We present a model for the intensity of optically thin EUV emission for a plasma atmosphere. We apply our model to the solar corona as observed using the six optically thin EUV channels of the SDO/AIA instrument. The emissivity of the…
Partially-ionized plasmas consist of charged and neutral particles whose mutual collisions modify magnetic reconnection compared with the fully-ionized case. The collisions alter the rate and locations of the magnetic dissipation heating…
Why the tenuous solar outer atmosphere, or corona, is much hotter than the underlying layers remains one of the greatest challenge for solar modeling. Detailed diagnostics of the coronal thermal structure come from extreme ultraviolet (EUV)…