相关论文: Non-thermal recombination - a neglected source of …

Brown and Mallik (BM) recently showed that, for hot sources, recombination of non-thermal electrons (NTR) onto highly ionised heavy ions is not negligible compared to non-thermal bremsstrahlung (NTB) as a source of flare hard X-rays (HXRs)…

Brown & Mallik 2008 and the Brown et al. 2010 corrigendum of it presented expressions for non-thermal recombination (NTR) in the collisionally thin- and thick-target regimes, claiming that the process could account for a substantial part of…

We have calculated nonthermal bremsstrahlung (NTB) models for the hard X-ray (HXR) tails recently observed by BeppoSAX in clusters of galaxies. In these models, the HXR emission is due to suprathermal electrons with energies of about 10-200…

We have measured electron-ion recombination for Fe$^{9+}$ forming Fe$^{8+}$ and for Fe$^{10+}$ forming Fe$^{9+}$ using merged beams at the TSR heavy-ion storage-ring in Heidelberg. The measured merged beams recombination rate coefficients…

We have investigated the effects of a non-thermal electron population on the ionization and recombination rates. The considered electron distribution is defined as a Maxwellian function below a break energy E_b and as a power-law function…

We have measured electron-ion recombination for Fe XII forming Fe XI using a merged beams configuration at the heavy-ion storage ring TSR located at the Max Planck Institute for Nuclear Physics in Heidelberg, Germany. The measured merged…

We have carried-out a series of multi-configuration Breit-Pauli AUTOSTRUCTURE calculations for the dielectronic recombination of Fe^{13+}. We present a detailed comparison of the results with the high-energy resolution measurements reported…

Unified recombination cross sections and rates are computed for (e + Fe XVIII) --> Fe XVII including non-resonant and resonant (radiative and di-electronic recombination, RR and DR) processes in an ab initio manner with relativistic fine…

We make the first observation-based calculation of the energy that goes into cosmic-ray protons versus cosmic ray electrons in shock acceleration during structure formation. We find a ratio of energy in cosmic ray protons to energy in…

In this paper we investigate the feasibility of bremsstrahlung radiation from `nonthermal' electrons as a source of hard X-rays from the intracluster medium of clusters of galaxies. With an exact treatment of the Coulomb collisions in a…

We present high quality optical spectroscopic observations of the planetary nebula (PN) Hf 2-2. The spectrum exhibits many prominent optical recombination lines (ORLs) from heavy element ions. Analysis of the H {\sc i} and He {\sc i}…

Extending previous studies of nonthermal electron transport in solar flares which include the effects of collisional energy diffusion and thermalization of fast electrons, we present an analytic method to infer more accurate estimates of…

A primary characteristic of solar flares is the efficient acceleration of electrons to nonthermal deka-keV energies. While hard X-Ray (HXR) observation of bremsstrahlung emission serves as the key diagnostic of these electrons. In this…

The study of X-ray reprocessing is one of the key diagnostic tools to probe the environment in X-ray binary systems. One difficult aspect of studying X-ray reprocessing is the presence of much brighter primary radiation from the compact…

The theoretical intensities of the soft X-ray Fe XVII lines arising from 2l-3l' transitions are reexamined using a three-ion collisional-radiative model that includes the contributions to line formation of radiative recombination (RR),…

We have carried-out multi-configuration Breit-Pauli AUTOSTRUCTURE calculations for the dielectronic recombination (DR) of Fe^{8+} - Fe^{12+} ions. We obtain total DR rate coefficients for the initial ground-level which are an order of…

Although both electron-ion and electron-electron bremsstrahlung contribute to the hard X-ray emission from solar flares, the latter is normally ignored. Such an omission is not justified at electron (and photon) energies above $\sim 300$…

Recent spectroscopic models of active galactic nuclei (AGN) have indicated that the recommended electron-ion recombination rate coefficients for iron ions with partially filled M-shells are incorrect in the temperature range where these…

Photoionization and recombination cross sections and rate coefficients are calculated for Li-like Fe XXIV and He-like Fe XXV using the Breit-Pauli R-matrix (BPRM) method. A complete set of total and level-specific parameters is obtained to…

We use ultrafast x-ray diffraction to study non-equilibrium pathways of the phase transition in FeRh parametrized by the structural response. By increasing the pump-pulse duration beyond the electron-phonon coupling time, we suppress the…