Related papers: R-matrix electron-impact excitation data for the N…
We report energy levels, radiative rates (A-values) and lifetimes for the astrophysically-important Be-like ion C III. For the calculations, 166 levels belonging to the $n \le$ 5 configurations are considered and the {\sc grasp}…
We present extensive calculations of radiative transition rates and electron impact collision strengths for Fe II. The data sets involve 52 levels from the $3d\,^7$, $3d\,^64s$, and $3d\,^54s^2$ configurations. Computations of $A$-values…
We present R-matrix calculations of photoabsorption and photoionization cross sections across the K edge of the Li-like to Ca-like ions stages of Ni. Level-resolved, Breit-Pauli calculations were performed for the Li-like to Na-like stages.…
Low-energy electron impact excitations of N$_2$ molecules are studied using the fixed-bond R-matrix method based on state-averaged complete active space SCF orbitals. Thirteen target electronic states of N$_2$ are included in the model…
Spectral modelling of kilonovae (KNe) require large amounts of collisional excitation and photoionization atomic data for lowly ionised (neutral, singly and doubly ionised) species of heavy elements. Much of the data currently used is…
We describe the computer codes, developed at Vilnius University, for the calculation of electron-impact excitation cross sections, collision strengths, and excitation rates in the plane-wave Born approximation. These codes utilize the…
We present results for the inner-shell electron-impact excitation of Fe$^{15+}$ using the intermediate-coupling frame transformation {\it R}-matrix approach in which Auger-plus-radiation damping has been included. The target and…
We report calculations of energy levels, radiative rates and electron impact excitation cross sections and rates for transitions in He-like Kr XXXV. The GRASP (general-purpose relativistic atomic structure package) is adopted for…
New X-ray observatories (Chandra and XMM-Newton) are providing a wealth of high-resolution X-ray spectra in which hydrogen- and helium-like ions are usually strong features. We present results from a new collisional-radiative plasma code,…
This work reports radiative transition rates and electron impact excitation rate coefficients for levels of the n= 3, 4, 5, 6, 7, 8 configurations of Ca II. The radiative data were computed using the Thomas-Fermi-Dirac central potential…
The growing interest in atomic structures of moderately-stripped alkali-like ions in diagnostic study and modeling of astrophysical and laboratory plasma makes an accurate many-body study of atomic properties inevitable. This work presents…
Fe II emission lines are observed from nearly all classes of astronomical objects over a wide spectral range from the infrared to the ultraviolet. To meaningfully interpret these lines, reliable atomic data are necessary. In work presented…
A unified scheme using the R-matrix method has been developed for electron-ion recombination subsuming heretofore separate treatments of radiative and dielectronic recombination (RR and DR). The ab initio coupled channel approach unifies…
Modeling the spectral emission of low-charge iron group ions enables the diagnostic determination of the local physical conditions of many cool plasma environments such as those found in H II regions, planetary nebulae, active galactic…
We present a comprehensive study of electron collisions with calcium atoms by using the convergent \emph{B}-spline \emph{R}-matrix method. Elastic, excitation, and ionization cross sections were obtained for all transitions between the…
We have carried-out 98-level configuration-interaction / close-coupling (CI/CC) intermediate coupling frame transformation (ICFT) and Breit-Pauli R-matrix calculations for the electron-impact excitation of Be-like Al$^{9+}$. The close…
This paper presents a theoretical investigation of the cross sections for dissociative electron attachment and dissociative excitation processes in vibrationally excited CH radicals induced by electron impact. Resonant electron-CH…
CHIANTI contains a large quantity of atomic data for the analysis of astrophysical spectra. Programs are available in IDL and Python to perform calculation of the expected emergent spectrum from these sources. The database includes atomic…
Neutral tungsten is the primary candidate as a wall material in the divertor region of the International Thermonuclear Experimental Reactor (ITER). The efficient operation of ITER depends heavily on precise atomic physics calculations for…
Modelling of massive stars and supernovae (SNe) plays a crucial role in understanding galaxies. From this modelling we can derive fundamental constraints on stellar evolution, mass-loss processes, mixing, and the products of…