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Full-Text Articles in Physics
Numerical Methods For Free-Free Radiative Transition Matrix Elements, Bo Gao, Anthony F. Starace
Numerical Methods For Free-Free Radiative Transition Matrix Elements, Bo Gao, Anthony F. Starace
Anthony F. Starace Publications
Increasing interest in multiphoton absorption processes above the ionization threshold has led theorists to reexamine numerical techniques for calculating radiative transition matrix elements between states of a continuum electron moving at large radial distances in the field of an atom or an ion. Here it is shown that accurate free-free radial matrix elements may be obtained using the usual dipole length formula by means of a rotation at finite distance in the complex coordinate plane together with solution of the free-electron wave function's phase and amplitude at finite distance in the complex coordinate plane. The procedure is designed for use …
Transition-Matrix Theory For Two–Photon Ionization Of Rare–Gas Atoms And Isoelectronic Ions With Application To Argon, Anthony F. Starace, Tsin-Fu Jiang
Transition-Matrix Theory For Two–Photon Ionization Of Rare–Gas Atoms And Isoelectronic Ions With Application To Argon, Anthony F. Starace, Tsin-Fu Jiang
Anthony F. Starace Publications
A transition-matrix theory for two-photon ionization processes in rare-gas atoms or isoelectronic ions is presented. Uncoupled ordinary differential equations are obtained for the radial functions needed to calculate the two-photon transition amplitude. The implications of these equations are discussed in detail. In particular, the role of correlations involving virtually excited electron pairs, which are known to be essential to the description of single-photon processes, is examined for multiphoton ionization processes. Additionally, electron scattering interactions between two electron-hole pairs are introduced into our transition amplitude in the boson approximation since these have been found important in two-photon ionization of xenon by …
Comment On "Molecular Description Of Two-Electron Atoms", Anthony F. Starace, Joseph H. Macek
Comment On "Molecular Description Of Two-Electron Atoms", Anthony F. Starace, Joseph H. Macek
Anthony F. Starace Publications
Molecular Description of Two-Electron Atoms
Atomic Hydrogen In A Uniform Magnetic Field: Low-Lying Energy Levels For Fields Above 109 G , Chih-Ray Liu, Anthony F. Starace
Atomic Hydrogen In A Uniform Magnetic Field: Low-Lying Energy Levels For Fields Above 109 G , Chih-Ray Liu, Anthony F. Starace
Anthony F. Starace Publications
The energies and wave functions of the 1s, 2s, 2p(ml=0), and 2p(ml=±1) levels of hydrogen in a uniform magnetic field B (109 G≤B≤1012 G) are calculated in two cylindrical adiabatic approximations, each of which includes the influence of the Coulomb field on the radial motion of the electron. For the lowest levels of each symmetry [i.e., the 1s, 2p(ml=0) and 2p(ml=±1) levels] our calculations provide rigorously both upper and lower bounds on the true level energies and binding energies. We …
Electron Correlation Effects In Nonresonant Multiphoton Ionization Processes, Anthony F. Starace
Electron Correlation Effects In Nonresonant Multiphoton Ionization Processes, Anthony F. Starace
Anthony F. Starace Publications
The role of electron correlations in nonresonant multiphoton processes of atoms is presented. The evidence for the validity of a lowest order perturbation theory (LOPT) approach for the laser field in the case of nonresonant processes is sketched. The growing consensus for a LOPT interpretation of even the multiply-charged ion spectra obtained with high intensity lasers is reviewed. Finally, a review of those specific electron correlation processes within LOPT that are important for the quantitative prediction of two-photon ionization cross sections is presented and some of their effects on calculated generalized cross sections are exhibited.