A fresh computational approach to atomic structures, processes and cascades

Abstract Electronic structure computations of atoms and ions have a long tradition in physics with applications in basic research, spectroscopy, life sciences and technology. Various theoretical methods (and codes) have therefore been developed to account for the many-particle structure of atoms, from simple semi-empirical estimates to accurate predictions of selected data, and up to highly advanced time-independent and time-dependent numerical techniques. — Here, I present a fresh concept and implementation of (relativistic) atomic structure theory that supports the computation of interaction amplitudes, properties as well as a large number of excitation and decay processes for open-shell atoms and ions across the whole periodic table. This implementation will facilitate also studies on atomic cascades, responses as well as the time-evolution of atoms and ions. It is based on Julia, a new programming language for scientific computing, and provides an easy-to-use but powerful platform to extent atomic theory towards new applications.

[1]  Stephan Fritzsche,et al.  Determination of small level splittings in highly charged ions via angle-resolved measurements of characteristic x rays , 2014 .

[2]  Stephan Fritzsche,et al.  Auger decay of 4d inner-shell holes in atomic Hg leading to triple ionization , 2017 .

[3]  I. P. Grant,et al.  New version: Grasp2K relativistic atomic structure package , 2013, Comput. Phys. Commun..

[4]  S. Fritzsche,et al.  Reply to “Comment on ‘Hyperfine-induced modifications to the angular distribution of the K α 1 x-ray emission’ ” , 2015 .

[5]  Walter Curtis Johnson,et al.  Relativistic Quantum Theory of Atoms and Molecules: Theory and Computation , 2008 .

[6]  S. Pabst,et al.  Calculation of photoelectron spectra within the time-dependent configuration-interaction singles scheme , 2014, 1403.0352.

[7]  Alan Edelman,et al.  Julia: A Fresh Approach to Numerical Computing , 2014, SIAM Rev..

[8]  Ari Jokinen,et al.  Ground state properties of manganese isotopes across the N=28 shell closure , 2010 .

[9]  Charlotte Froese Fischer,et al.  DBSR_HF: A B-spline Dirac-Hartree-Fock program , 2016, Comput. Phys. Commun..

[10]  B. Heckel,et al.  Reduced Limit on the Permanent Electric Dipole Moment of ^{199}Hg. , 2016, Physical review letters.

[11]  Stephan Fritzsche,et al.  Two-photon double ionization of Ne by free-electron laser radiation: a kinematically complete experiment , 2009 .

[12]  E. Gaidamauskas,et al.  Tensorial form and matrix elements of the relativistic nuclear recoil operator , 2011, 1106.1988.

[13]  J T Costello,et al.  Two-photon excitation and relaxation of the 3d-4d resonance in atomic Kr. , 2010, Physical review letters.

[14]  Walter R. Johnson,et al.  Atomic Structure Theory : Lectures on Atomic Physics , 2007 .

[15]  Stephan Fritzsche,et al.  Triple ionization of atomic Cd involving 4p(-1) and 4s(-1) inner-shell holes , 2015 .

[16]  Joseph Sucher.  Magnetic dipole transitions in atomic and particle physics: ions and psions , 1978 .

[17]  A. N. Artemyev,et al.  Relativistic nuclear recoil corrections to the energy levels of multicharged ions , 1994 .

[18]  Stephan Fritzsche,et al.  Auger cascades in resonantly excited neon , 2017 .

[19]  Fritzsche,et al.  Reduced L1 level width and Coster-Kronig yields by relaxation and continuum interactions in atomic zinc. , 1992, Physical review. A, Atomic, molecular, and optical physics.

[20]  T. Buhr,et al.  Stepwise contraction of the nf Rydberg shells in the 3d photoionization of multiply-charged xenon ions , 2014, 1412.3592.

[21]  Gediminas Gaigalas,et al.  An MCHF atomic-structure package for large-scale calculations , 2007, Comput. Phys. Commun..

[22]  Stephan Fritzsche,et al.  The Ratip program for relativistic calculations of atomic transition, ionization and recombination properties , 2012, Comput. Phys. Commun..

[23]  Fischer,et al.  Transition probability calculations for atoms using nonorthogonal orbitals. , 1995, Physical review. E, Statistical physics, plasmas, fluids, and related interdisciplinary topics.

[24]  Heller,et al.  Overrelaxation and mode coupling in sigma models. , 1989, Physical review. D, Particles and fields.

[25]  R. D. Cowan,et al.  The Theory of Atomic Structure and Spectra , 1981 .

[26]  Stephan Fritzsche,et al.  REOS — A program for relaxed-orbital oscillator strength calculations , 1997 .

[27]  Klein,et al.  Plasma diagnostics with spectral profile calculations. , 1994, Physical review. E, Statistical physics, plasmas, fluids, and related interdisciplinary topics.

[28]  Gediminas Gaigalas,et al.  GRASP2018 - A Fortran 95 version of the General Relativistic Atomic Structure Package , 2019, Comput. Phys. Commun..

[29]  I. P. Grant,et al.  Program to calculate pure angular momentum coefficients in jj-coupling☆ , 2001, physics/0405129.

[30]  Ian P. Grant,et al.  A program for the complete expansion of jj-coupled symmetry functions into Slater determinants , 1995 .

[31]  V. V. Balashov,et al.  Polarization and Correlation Phenomena in Atomic Collisions , 2000 .

[32]  Bradley Cheal,et al.  Laser spectroscopy of radioactive isotopes: Role and limitations of accurate isotope-shift calculations , 2012 .