Most Recent

We investigate single-electron capture in collisions between bare Ne${}^{10+}$ ions and hydrogen atoms initially prepared in the $n=2$ excited state. Total and principal-quantum-number-resolved capture cross-sections are calculated with the classical-trajecto...

The P-wave resonance states of the positronium negative ion Ps⁻ embedded in non-ideal classical plasmas are investigated using the stabilization method. Effective interparticle interactions are modeled via a non-ideal plasma pseudopotential acc...

Measuring the timing of photoionization requires understanding how light-driven electron motion is encoded in the detected electron distribution. In this work, we present a theoretical study of a laser-assisted attoclock, in which a short extreme-ult...

Charlotte Froese Fischer and Ian Philip Grant were both eminent in the numerical treatment of atomic structure theory. How do they still guide future work in “my” research sector, experimental atomic spectroscopy and lifetime measurements...

The field of matter wave interferometry is rapidly advancing on multiple frontiers [...]

A collection of short stories about Barry Irwin Schneider (1940–2024), to whom this Special Issue of Atoms is dedicated.

The Exponentially Correlated Hylleraas–Configuration Interaction method (E-Hy-CI) is a generalization of the Hylleraas–Configuration Interaction method (Hy-CI), in which the single $r_{ij}$ is generalized to a form of the generic type $r_{ij}^{{\nu }_i}$...

We explore the parameter space of the pvCD-Bonn B potential within the relativistic Brueckner–Hartree–Fock framework under the constraints from the empirical saturation properties of symmetric nuclear matter. We first examined the effects...

An empirical model of the TU Muscae binary star system has been developed by a study of 23 high resolution SWP spectrophotometric images that were obtained with the International Ultraviolet Explorer (IUE) satellite telescope including some that were...

The Atomic Lunar Seismometer (ALS) is an atom-interferometer instrument concept for measuring the lunar gravity and vibration modes at long time scales. Compared to other seismometer techniques, atom interferometers offer a pathway toward an ultra-lo...

Accurate atomic data for heavy ions are required for spectroscopic diagnostics and impurity transport modeling in magnetic-confinement fusion devices, particularly for tungsten and its neutron-induced transmutation products. In the present work, we i...

In this work, we report a high-precision experimental determination of the ratio $g_{F,D}/g_{F,S}=0.998060\left(5\right)$ between the Landé g-factors for states ${}_{}{}^{2}S_{1/2}^{}(F=1)$ and ${}_{}{}^{2}D_{3/2}^{}(F=1)$ in ¹⁷¹Yb⁺. Together with the recently calculated g-factor of the ${}_{}{}^{2}S_{1/2}^{}$ stat...

Precision tests of the Standard Model at low energy are increasingly limited by nuclear-structure theory rather than by experiments. We review two such cases: the two-photon-exchange correction to the Lamb shift in muonic atoms, and the γW box...

We present a computational framework for constructing effective, intrinsically screened heavy-particle potentials in dense plasmas from first-principles pseudopotentials. Starting from available projector-augmented-wave (PAW) data in the Unified Pseu...

Building on our previous multi-configuration Dirac–Hartree–Fock (MCDHF) computational strategies tailored for the hyperfine structure (HFS) of low-lying levels in one-valence electron Sr II and Ba II ions and in two-valence electrons in a...

In scattering and tunnelling-to-continuum problems, the regular and irregular solution pairs to the one-particle radial Schrödinger equation follow various amplitude and phase difference conventions at infinity. The Milne transformation of the S...

An algorithm for large-scale correlated calculations on atoms is presented that significantly reduces the scaling of these calculations with the number of single-particle functions used to construct the N-particle states. The reduction is provided in...

We present an ab initio quadrupole-invariant study of neutron-rich nuclei around $N=28$. Effective Hamiltonians and consistently evolved $E2$ operators are obtained from chiral NN+3N interactions using the ab initio valence-space in-medium similarity ren...

We investigate reactive collision dynamics and effective interaction cross-sections using classical trajectory simulations on a reduced-dimensional reactive potential-energy surface containing reactant and product wells separated by an intermediate b...

Space-based navigation systems rely on atomic clocks aboard satellites to provide precise time and positioning information through synchronized radio-frequency signals. At the core are Atomic Frequency References (AFRs), which stabilize a local oscil...

We outline an intermediate step toward a semirelativistic BSR–RMT interface by using inner-region structure information generated with the B-spline R-matrix (BSR) method as the input to the Seaton/Badnell STGF/STGBF outer-region asymptotic code...

Quantum relativistic solutions of a “square-root” version of the Klein–Gordon equation, for a particle in a one-dimensional Morse potential, are presented using methods previously proposed and applied to a particle in a harmonic osc...

In the present work, configuration assignments to K = 1/2 bandheads of given three-quasiparticle (3qp) quadruplets experimentally observed and yet to be observed in odd-A nuclei lying in the rare-earth mass region are carried out based on an improved...

Mass measurements of isotopes around the $A=184$ region near stability were performed at the KEK Isotope Separation System within the RIKEN Nishina Center, Japan. The isotopes were produced via multi-nucleon transfer reactions with a ¹³⁶Xe beam of 7.2...

Tailoring the spatial and angular-momentum structure of high-harmonic radiation is an important route toward controllable extreme-ultraviolet structured light. Here, we introduce an orbital angular momentum (OAM)-resolved photon-channel framework to...

Single-electron capture in the collisions of carbon ions, ${\mathrm{C}}^{q+}$ (q = 1–6), with water molecules is theoretically investigated using the continuum distorted wave-eikonal initial state (CDW-EIS) formalism. The projectile–electron interaction...

Earlier work by some of the present authors identified power-law statistical regularities across the periodic table: a near-Zipf relationship $W\propto Z^{1.09}$ between atomic weight and atomic number in neutral atoms, and a fine-structure splitting scalin...

The Bohr radius is normally presented as a non-relativistic length scale. Less widely discussed is that Bohr’s 1913 work also indicated how the radius formula changes when the orbital velocity is not negligible compared with the speed of light....

The distorted-wave approach is applied to electron impact single ionization of krypton. We find that our models CPE4 and DW2 give results which are in fair agreement with the experiments. Both models contain a final state representation which include...

We present an extensive set of theoretical results for spin asymmetry in the form of Sherman functions for the elastic scattering of electrons by zinc, cadmium, and mercury. This study extends the application to these three atoms of our earlier metho...

Single-electron emission from the coronene (C₂₄H₁₂) molecule induced by the impact of 100 keV H⁺ projectiles is investigated using the continuum distorted wave–eikonal initial state approximation within a semi-classical impact-parameter framewo...

In this work, we implement the finite-field (FF) method for isotope shift (IS) calculations within the relativistic multiconfiguration Dirac–Hartree–Fock (MCDHF) framework of the GRASPG program package. The implementation is benchmarked u...

Molecular tunnel ionization sets the stage for the subsequent attosecond processes. Therefore, a comprehensive understanding of its dependence on various molecular properties, such as binding energy, wave function shape, dipole moment, and polarizabi...

Spectral line shapes are used to diagnose parameters of white dwarfs and neutron stars in particular. In magnetized plasmas, the motion of the radiating atom in the plasma needs to be considered in the collision process as the electronic structure of...

This work presents an extension of the Belgrade ACol collisional database within the Virtual Atomic and Molecular Data Centre (VAMDC) framework to include dissociative electron attachment (DEA) processes. DEA, a low-energy electron-driven resonant me...

The critical binding of quantum states in Screened Coulomb Potentials such as Yukawa/Debye, Hulthén, and ECSC (Exponential Cosine Screened Coulomb) potentials is of perennial interest and relevance in many fields of science, ranging from nucle...

We present an extensive set of theoretical results for differential, integrated, and momentum-transfer cross sections for the elastic scattering of electrons by zinc, cadmium, and mercury. Our approach is a self-consistent relativistic calculation, w...

We theoretically study the single ionization of liquid water by impact of fast electrons. A realistic description of the wavefunction for an isolated water molecule in the liquid phase is obtained by means of a Wannier orbital formalism. In this way,...

Ionization potentials and electron affinities provide the energetic basis for several conceptual density functional theory descriptors, but their use in donor–acceptor maps requires careful distinction between physically bound anions, weak or b...

We present a theoretical study focused on the photoelectron spectrum of near-infrared (NIR) laser-driven ionization of hydrogen atoms by attosecond pulse trains composed of several HHs of the former. We analyze the effects of increasing the intensity...

Electron configurations are known to provide valuable insights into the electronic structure and behavior of atoms. They specify which and how the electronic (sub-) shells are occupied, and are thus an essential ingredient for most atomic observables...

Ian Philip Grant (see Figure 1) was a monumental figure in relativistic atomic and molecular atomic physics [...]

Total, momentum-transfer, and differential cross sections, together with spin-polarization (Sherman) functions, are reported for elastic scattering of low-energy electrons from neutral strontium atoms over the energy range 0.001–15 eV. The calc...

We study exotic orbits in the photoassociation process by considering both the vibrational and rotational motions in a classical model. In the presence of rotational motion, the exotic orbits possess regular bound segments even when the total energy...

In this work, state-selective electron-capture processes in collisions of Ar¹⁶⁺ with ground-state hydrogen are analyzed in classical terms by means of the classical trajectory Z-CTMC method. Oscillations in the n-state-selective charge-exchange cross...

Electron emission from hydrogen atoms induced by antiproton impact at intermediate energies is investigated using the one-centre Basis Generator Method within a semi-classical impact-parameter framework. The formulation employs a single-centre expans...

A developed method, based on the stationary second-order Rayleigh–Schrödinger many-body perturbation theory in an irreducible tensorial form, allows us to determine the most important core–valence, core, core–core, and valence&...

Laser-induced breakdown in water-rich biological media results from the interplay between primary photoionization processes and avalanche amplification of free electrons. Understanding this competition is essential for predicting ablation thresholds...

Resonant transfer and excitation (RTE) is a correlated two-electron ion–atom collision process mediated by the two-center electron–electron interaction: a projectile electron is excited while a target electron is captured, forming doubly...

We propose an analytical model and perform numerical simulations to study the time distribution of the characteristic muonic oxygen X-ray emission following muon transfer from muonic hydrogen to oxygen in a H₂ + O₂ gas mixture. The model accounts for...