Atoms, Volume 11, Issue 3

Stellar atmospheres separate the hot and dense stellar interiors from the emptiness of space. Radiation escapes from the outermost layers of a star, carrying direct physical information. Underneath the atmosphere, the very high opacity keeps radiatio...

Heteronuclear diatomic rare gas molecular cations feature excited electronic terms with charge transfer character located several eV above the ground term. The role of such terms in collisions involving heteronuclear ions is studied theoretically und...

Werner Eissner (Figure 1), a pioneer in computational atomic physics, was born on 16 October 1930 in the city of Görlitz, Germany, to Bernhard and Frieda (née Eckert) Eissner [...]

We report measurements of hypersatellite radiation of argon ions in the electron energy region of 5200 eV to 7500 eV. Here, we observed a strong enhancement of this hypersatellite ${\mathrm{K}}_{\alpha }^h$ production. Trielectronic recombination (TR) is discussed as a pos...

To provide spectroscopic data for W${}^{13+}$, the present work is focused on the analysis of spectra observed in the visible range, using a compact electron beam ion trap (CoBIT). Line identification is done by using a collisional radiative model, along wi...

Here, we present evidence that the D_2h M₂C₅^0/2+ (M = Li-K, Be-Ca, Al-In, and Zn) species comprises planar hexacoordinate carbon (phC) structures that exhibit four covalent and two electrostatic interactions. These findings have been made possible usi...

The positron impact cross-sections of pyrimidine molecules are reported from 1 eV to 5000 eV. These cross-sections include differential elastic, integral elastic, and direct ionisation. The elastic cross-sections are computed using the single-centre...

Photoionization and its inverse, electron–ion recombination, are key processes that influence many astrophysical plasmas (and gasses), and the diagnostics that we use to analyze the plasmas. In this review we provide a brief overview of the imp...

The application of a neutral particle analyzer (NPA) diagnostic at the Globus-M/M2 spherical tokamaks is discussed. Physical principles of the diagnostic are reviewed. Two general approaches—active and passive measurements—are described....

Opacity determines radiation transport through material media. In a plasma source, the primary contributors to atomic opacity are bound–bound line transitions and bound-free photoionization into the continuum. We review the theoretical methodol...

The use of atom interferometers in inertial systems holds the promise of improvement of several orders of magnitude in sensitivity over sensors using current technology such as micro-electro-mechanical (MEMS) devices or ring laser gyroscopes (RLGs)....

Radiative recombination (RR) plasma rate coefficients are often applied to estimate electron densities and temperatures under quite different plasma conditions. Despite their frequent use, however, these rate coefficients are available only for selec...

We measure double differential cross sections (DDCS) of electrons emitted from CH₄ molecules in collisions with 250 keV protons. The projectile ions are obtained from a 400 kV electron cyclotron resonance-based ion accelerator (ECRIA). We study the e...

Extreme ultraviolet spectra of Na-like and Mg-like Os and Ir were recorded at the National Institute of Standards and Technology using a grazing incidence spectrometer. We report a method in EBIT spectral analysis that reduces signals from contaminan...

Dramatically sharp resonances manifesting stable negative ion formation characterize Regge pole-calculated low-energy electron elastic total cross sections (TCSs) of heavy multi-electron systems. The novelty of the Regge pole analysis is in the extra...

We present theoretical studies of electron and positron interaction with protons aligned in a one-dimension periodic line. The equally spaced protons were artificially generated where the individual protons are fixed in a certain position. The incide...

Beam–foil extreme-ultraviolet survey spectra of Ge ($Z=32$) are presented. The data have been garnered at the performance limit of the heavy-ion accelerator available, with a correspondingly limited statistical and calibrational reliability. Howe...

In an effort to measure electron-impact ionization (EII) cross-sections of He-like $F{e}^{24+}$ at the electron beam ion trap (EBIT) facility of the National Institute of Standards and Technology (NIST), we have experimentally determined the corrections to...

We report measurements and identification of the E3 4f${}_{7/2,5/2}$-5s${}_{1/2}$ transitions and E1 allowed transitions in Ag-like W (Z = 74), Re (Z = 75), and Ir (Z = 77). The spectra were recorded at the NIST EBIT using a grazing-incidence EUV spectrometer. The...

We study the dynamical evolution of quantum Fisher information (QFI) and von Neumann entropy (VNE) for a three-level atomic system interacting with the single-mode coherent field in the presence of the Stark effect and intrinsic decoherence (ID) with...

The shake-off processes and charge-state fractions of ${}^6$Li${}^{+}$, ${}^6$Li${}^{++}$, and ${}^6$Li${}^{3+}$ were studied following the beta decay of ${}^6$He in the $1s^2{}^1{S}_0$, $1s2s{}^1{S}_0$, and $1s2s{}^3{S}_1$ initial states. The sudden approximation was used, together with fully correlated Hylleraas...