Comprehensive collisional radiative (CR) models have been developed for the diagnostic of argon plasma using Ar and Ar+ emission lines. The present CR models consist of 42 and 114 fine-structure levels of Ar and Ar+, respectively. Various populating...
Ni iv lines can be used as diagnostics for temperature and density for various astrophysical objects. In addition, ionization of Ni2+ is one of the causes of the opacity in the interstellar medium. We calculate the photoionization of Ni2+ and the ele...
The results of experimental and theoretical studies on electron-impact excitation of the 6s6p P1° 3→6s2 S0 1 (λ190.8 nm) and 6s7s S0 1→6s6p P1° 3 (λ179.9 nm) intercombination tra...
An abundance of absorption and emission lines of iron-peak species such as Fe I and Fe II can be seen in the spectra of many astrophysical objects. Thus, the accurate modelling of such spectra requires sets of high quality atomic data for these speci...
Results of experimental and theoretical investigation of electron-impact excitation of the 6s26d D2→6s26p P2o spectral transitions from the ground 6s26p P21/2o level in the Pb+ ion are presented. The experimental excitation...
We present convergent close-coupling (CCC) calculations of electron-impact dissociation of vibrationally-excited molecular hydrogen into neutral fragments. This work follows from our previous results for dissociation of molecular hydrogen in the grou...
Electron impact excitation of highly charged tungsten ions in the framework of a fully relativistic distorted wave approach is considered in this paper. Calculations of electron impact excitation cross-sections for the M- and L-shell transitions in t...
Electron impact excitation (EIE) and dielectronic recombination (DR) of tungsten ions are basic atomic processes in nuclear fusion plasmas of the International Thermonuclear Experimental Reactor (ITER) tokamak. Detailed investigation of such processe...
The excitation cross sections of the 2P state of atomic hydrogen at low incident electron energies (from 0.755 to 3.5 Ry) were calculated using the variational polarized orbital method. Up to 13 partial waves (L = 1, 13) were used to obtain converged...
The excitation cross sections of the 2S state of atomic hydrogen at 10 low incident electron energies (10.30 and 54.5 eV) have been calculated using the variational polarized method. Nine partial waves are used to get convergence of cross sections in...
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...
The excitation cross-sections of the nS states of atomic hydrogen, n = 2 to 6, by electron impact on the ground state of atomic hydrogen were calculated using the variational polarized-orbital method at various incident electron energies in the range...
We study electron impact excitation of dipole allowed transitions in the extreme ultraviolet range—8–55 nm—for the germanium isoelectronic sequence Te20+–Cd16+. The fine structure transitions between the ground state having co...
In one of our previous papers, we performed a comparative analysis of the experimental and theoretical cross-sections for the excitation of atomic hydrogen by electrons. We found that the theoretical ratio of the cross-section σ2s of the excita...
We revisit the current status of high-precision calculations for electron-impact excitation of the (1s3s)3,1S states in helium in the low-energy near-threshold regime that is characterized by a large number of resonance features. Having noticed discr...
Systematic R-matrix calculations of electron-impact excitation for ions of astrophysical interest have been performed since 2007 for many iso-electronic sequences as part of the UK Atomic Process for Astrophysical Plasma (APAP) network. Rate coeffici...
The online atomic database of NORAD-Atomic-Data, where NORAD stands for Nahar OSU Radiative, is part of the data sources of the two international collaborations of the Opacity Project (OP) and the Iron Project (IP). It contains large sets of paramete...
For the excitation of the n = 2 states of hydrogen atoms due to electron impact, we compared the experimental and theoretical ratios of the cross-sections σ2s/σ2p. We found this theoretical ratio to be systematically higher than the corre...
The excitation cross-sections of the 3D and 4D states of atomic hydrogen at low incident energies (from 0.90 to 5.00 Ry) were calculated using the variational polarized orbital method, which is also called the hybrid theory. Up to 12 partial waves (L...
We report cross-sections and rate coefficients for excited states colliding with electrons, heavy particles and walls useful for the description of H 2 /He plasma kinetics under different conditions. In particular, the role of the rotational s...
We present a theoretical investigation of the inelastic scattering of vortex electrons by many-electron atoms embedded in a solid-state environment. Special emphasis is placed on the probability of exciting a target atom and on the relative populatio...
We report recent enhancements to the online atomic database at the Ohio State University, NORAD-Atomic-Data, that provide various parameters for radiative and collisional atomic processes dominant in astrophysical plasma. NORAD stands for Nahar Osu R...
Cross sections and thermally averaged rate coefficients for the vibrational excitation and de-excitation by electron impact on the HDO molecule are computed using a theoretical approach based entirely on first principles. This approach combines scatt...
Electron impact excitation collision strengths are calculated for all transitions among 113 levels of the 2s 2 2p 5 , 2s2p 6 , 2s 2 2p 4 3ℓ, 2s2p 5 3ℓ, and 2p 6 3ℓ configurations of F-like W LXVI. For...
In the present work, a detailed study on the electron impact excitation of Xe7+, Xe8+, Xe9+ and Xe10+ ions for the dipole allowed (E1) transitions in the EUV range of 8–19 nm is presented. The multi-configuration Dirac–Fock method is used for the ato...
Cross-sections and thermally averaged rate coefficients for vibration (de-)excitation of a water molecule by electron impact are computed; one and two quanta excitations are considered for all three normal modes. The calculations use a theoretical ap...
Cross sections for rotational excitation and de-excitation of the HeH+ ion by an electron impact are computed using a theoretical approach that combines the UK R-matrix code and the multi-channel quantum defect theory. The thermally-averaged rate coe...
Cross sections and thermally-averaged rate coefficients for vibration (de-)excitation of HeH + by an electron impact are computed using a theoretical approach that combines the multi-channel quantum defect theory and the UK R-matrix code. Fit...
Cross sections and thermal rate coefficients for rotational and vibration excitation of the four stable isotopologues of the 4 HeH + ion by electron impact are presented. The data are calculated using a previously developed theoretica...
The spectra currently emerging from modern ground- and space-based astronomical instruments are of exceptionally high quality and resolution. To meaningfully analyse these spectra, researchers utilise complex modelling codes to replicate the observat...
The electron impact excitation and ionization processes are crucial for modeling the spectra of different astrophysical objects, from atmospheres of late-type stars to remnants of supernovae and up to the light emission from neutron star mergers, to...
In this work, a krypton gas impurity seeding experiment was conducted in a Large Helical Device. Emission lines from the Na-like Kr ion in the extreme ultraviolet wavelength region, such as 22.00 nm, 17.89 nm, 16.51 nm, 15.99 nm, and 14.08 nm, respec...
In a recent paper, Tayal et al. (Astrophys. J. Suppl. 2019, 242, 9) reported results for energy levels, radiative rates (A-values), and effective collision strengths ( Υ ) for transitions among the 198 levels of Si-like S III. For the cal...
The study of atomic spectroscopy and collision processes in a dense plasma environment has gained a considerable interest in the past few years due to its several applications in various branches of physics. The multiconfiguration Dirac-Fock (MCDF) m...
A collisional radiative model for Kr III in the ultraviolet regime is developed. For this purpose, atomic parameters for 4s24p4, 4s4p5, 4s24p3nl, and 4s24p35d configurations with n ranging from 5 to 7 and l=s,p, using the multiconfiguration Dirac&nda...
We report calculations of energy levels, radiative rates, collision strengths and effective collision strengths for transitions among the lowest 25 levels of the n ≤ 5 configurations of He II. The general-purpose relativistic atomic structure...
Protonated hydrogen cyanide, HCNH+, is one of the most important molecules of interest in the astrophysical and astrochemical fields. This molecule not only plays the role of a reaction intermediary in various types of interstellar reactions but was...
The excitation cross-sections of the 2S state of atomic hydrogen at low (near threshold energy) to high incident positron energies (10.30 to 300 eV) have been calculated using the variational polarized-orbital method. Nine partial waves have been use...
We use the PyNeb 1.1.16 Python package to evaluate the atomic datasets available for the spectral modeling of [Fe ii] and [Fe iii], which list level energies, A-values, and effective collision strengths. Most datasets are reconstructed from the sourc...
Pulsed gas injection in a plasma can affect many fundamentals, including electron heating and losses. The case of an asymmetric RF magnetron plasma with a pulsed argon injection is analyzed by optical emission spectroscopy of argon 2p-to-1s transitio...
In this paper, we present an experimental and theoretical study of excitation processes for the heaviest stable helium-like ion, that is, He-like uranium occurring in relativistic collisions with hydrogen and argon targets. In particular, we concentr...
The time-dependent close-coupling method has been recently applied to calculate electron-impact direct ionization cross sections for the Kr, W, and Pb atoms. An overview is presented for these three heavy neutral atom systems. When the direct ionizat...
Electron-impact ionization (EII) processes are essential for modelling high-temperature plasma in quite different research areas, from astrophysics to material science to plasma and fusion research and in several places elsewhere. In most, if not all...
The relativistic convergent close-coupling method is applied to calculate cross sections for electron scattering from atomic tin. We present integrated and momentum-transfer cross sections for elastic scattering from the ground and the first four exc...
We report calculations for electron–radon scattering using a complex relativistic optical potential method. The energy range of this study is 0–1000 eV, with results for the elastic (total, momentum-transfer and viscosity-transfer) cross...
The excitation cross sections of the nS states, n = 2 to 6, of atomic hydrogen at various incident positron energies (10.23 to 300 eV) were calculated using the variational polarized-orbital method. Nine partial waves were used to obtain converged cr...
The intensity ratio of Fe XIV 264.765A/274.203A is useful to determine the electron density of solar corona, and the relationship between the electron density and the intensity ratio obtained from a model should be evaluated using laboratory plasmas...
It has been known that the modification of non-metallic solid materials (oxides, nitrides, etc.), e.g., the formation of tracks, sputtering representing atomic displacement near the surface and lattice disordering are induced by electronic excitation...
Spectral line shapes are a key ingredient of hot-plasma opacity calculations. Since resorting to elaborate line-shape models remains prohibitive for intensive opacity calculations involving ions in different excitation states, with L, M, etc., shells...
PyNeb is a Python package widely used to model emission lines in gaseous nebulae. We take advantage of its object-oriented architecture, class methods, and historical atomic database to structure a practical environment for atomic data assessment. Ou...
of 4