Atomic Inner-Shell Physics

The physics of atomic inner shells has undergone significant advances in recent years. Fast computers and new experimental tools, notably syn­ chrotron-radiation sources and heavy-ion accelerators, have greatly enhan­ ced the scope of problems that are accessible. The level of research activity is growing substantially; added incentives are provided by the importance of inner-shell processes in such diverse areas as plasma studies, astrophysics, laser technology, biology, medicine, and materials science. The main reason for all this exciting activity in atomic inner-shell physics, to be sure, lies in the significance of the fundamental problems that are coming within grasp. The large energies of many inner-shell processes cause relativistic and quantum-electrodynamic effects to become strong. Unique opportunities exist for delicate tests of such phenomena as the screening of the electron self-energy and the limits of validity of the present form of the frequency-dependent Breit interaction, to name but two. The many-body problem, which pervades virtually all of physics, presents somewhat less intractable aspects in the atomic inner-shell regime: correlations are relatively weak so that they can be treated perturbatively, and the basic potential is simple and known! The dynamics of inner-shell processes are characterized by exceedingly short lifetimes and high transition rates that strain perturbation theory to its limits and obliterate the traditional separation of excitation and deexcitation. These factors are only now being explored, as are interference phenomena between the various channels.

A: Atomic Structure and Transitions.- 1 Relativistic and Quantum Electrodynamic Effects on Atomic Inner Shells.- 1. Introduction.- 2. Review of the Dirac-Fock Method.- 3. Breit Interaction.- 4. Quantum Electrodynamic Corrections.- 5. Conclusion.- References.- 2 Relativistic Calculation of Atomic Transition Probabilities.- 1. Introduction.- 2. The Relativistic Theory of Many-Electron Atoms.- 2.1. Relativistic Hamiltonian from Quantum Electrodynamics.- 2.2. Interpretation of the Dirac-Fock Approach.- 3. Relativistic Transition Energies.- 3.1. Atomic Binding Energies and X-Ray Transition Energies.- 3.2. Auger Energies.- 4. Radiative Transitions.- 4.1. Introduction.- 4.2. Formulation of Relativistic Radiative Transitions.- 4.3. Effects of Relativity, Retardation, and Higher Multipoles.- 4.4. Exchange and Overlap Corrections.- 4.5. K X-Ray Hypersatellites.- 5. Radiationless Transitions.- 5.1. Introduction.- 5.2. Relativistic Theory of Auger Transitions.- 5.3. Effects of Relativity on Auger Transitions.- 5.4. Analysis of K-LL and K-MM Auger Spectra.- 6. Auger and Fluorescence Yields of Multiply Ionized Atoms.- 6.1. Fluorescence Yields of Atoms with Multiple Vacancies.- 6.2. Effects of Relativity on the Decay of Few-Electron Ions.- 7. Summary.- References.- 3 Many-Body Effects in Energetic Atomic Transitions.- 1. Introduction.- 2. Higher-Energy Processes: Transitions from Inner Shells.- 2.1. Introduction.- 2.2. Binding Energy.- 2.3. Intensity.- 2.4. Satellites.- 3. Low-Energy Processes: Transitions from Subvalence Subshells.- 3.1. Weak Inner-Shell Transitions in the Presence of Strong Outer-Shell Transitions.- 3.2. Strong Inner-Shell Transitions with Weak Outer-Shell Transitions.- 4. Concluding Remarks.- References.- 4 Auger-Electron Spectrometry of Core Levels of Atoms.- 1. Introduction.- 2. Theory of Auger Transitions and Basic Considerations.- 2.1. Definitions and Notation.- 2.2. Theory of Auger Transitions; the Wentzel Ansatz.- 2.3. The Auger Effect Treated beyond the Wentzel Ansatz.- 3. Experimental Arrangements.- 4. Diagram Auger Transitions.- 4.1. Energies.- 4.2. Intensities.- 4.3. Linewidths.- 5. Auger Satellite Transitions Due to Many-Electron Effects.- 5.1. Satellite Transitions Due to Final-Ionic-State Configuration Interaction (FISCI).- 5.2. Satellite Transitions Due to Initial-State Configuration Interaction (ISCI)..- 6. Auger Spectra of Multiply Ionized Atoms.- 6.1. The (1s2p)-1 Auger Spectrum of Ne.- 6.2. Auger Spectra of Li-like Target Ions.- 7. Projectile Auger-Electron Spectrometry.- 8. Anisotropic Angular Distribution of Auger Electrons.- 8.1. Particle-Impact Experiments with Axial Symmetry.- 8.2. Photon-Impact Experiments with Axial Symmetry.- 8.3. Experiments with Plane Symmetry.- 9. Postcollision Interaction Effects in Auger Spectra.- References.- 5 Experimental Evaluation of Inner-Vacancy Level Energies for Comparison with Theory.- 1. Introduction and Overview.- 2. Methods for Determining Levels and Level Differences.- 2.1. Absorption Spectroscopy.- 2.2. Photoelectron and Auger-Electron Spectroscopies.- 2.3. Appearance-Potential Spectroscopy.- 2.4. X-Ray Emission Spectroscopy.- 3. Experimental Techniques for High-Accuracy Spectroscopy.- 3.1. Wavelength Determination in the Grating Region.- 3.2. Wavelength Problems in Crystal-Diffraction Spectroscopy.- 3.3. Local Scales and Conversion Factors.- 3.4. Wavelengths Based on X-Ray Interferometry.- 3.5. Wavelength Measurements with Focusing Instruments.- 4. Selected Experimental Results.- 4.1. Measurements from Direct-Reading Instruments.- 4.2. Measurements Referred to Directly Measured y-Ray Lines.- 4.3. Measurements Referred to Directly Measured X-Ray Lines.- 4.4. One-Electron and Few-Electron Spectra.- 5. Theoretical Calculations and Comparison with Experiment.- 5.1. Relativistic Self-Consistent-Field Calculations.- 5.2. Theoretical Relativistic SCF Estimates.- 5.3. Comparison with Experiment.- 5.4. Conclusions Derived from Comparison.- 6. Summary and Outlook.- 6.1. Relation between Single-Electron and X-Ray Spectra.- 6.2. Future Measurements and Applications.- References.- 6 Mechanisms for Energy Shifts of Atomic K X Rays.- 1. Introduction.- 2. The Experimental Method.- 3. The Isotope Shift.- 4. The Chemical Shift.- 4.1. Origin of the Chemical Shift.- 4.2. Examples of Data and Applications.- 5. The 1s Hyperfine Shift.- 5.1. Population of the Hyperfine-Structure Components in EC Beta Decay and Internal Conversion (IC).- 5.2. Experimental Observations of 1s Hyperfine Shifts.- 6. The Dynamic Shift.- 6.1. Outer-Shell Shake-Off and Its Effects on K X-Ray Energies.- 6.2. Experimental Detection of the Dynamic Shift.- 7. The Atomic Structure Shift for Transitions with ?Z= 1.- 7.1. The 6s Elements.- 7.2. The 4f Elements.- 7.3. The 4d Elements.- 7.4. The 5d Elements.- 8. Other Contributions.- 8.1. Deviations from the Breit-Wigner Single-Level Line Shape.- 8.2. The Coupling of Atomic and Nuclear Excitations.- 9. Concluding Remarks.- References.- 7 Atomic Physics Research with Synchrotron Radiation.- 1. Introduction.- 2. Synchrotron Radiation.- 3. Techniques.- 4. Many-Electron Effects.- 5. Excitation/Deexcitation Dynamics.- 6. Photoionization of Atoms in Excited States.- 7. Molecular Physics.- 8. Conclusion.- References.- 8 Investigations of Inner-Shell States by the Electron Energy-Loss Technique at High Resolution.- 1. Introduction.- 1.1. Early Inner-Shell Excitation Studies.- 1.2. High-Resolution Studies.- 1.3. Comparison of the Photoabsorption and Electron Energy-Loss Techniques.- 2. Experimental Details.- 2.1. Electron Source and Energy Selector.- 2.2. Energy Analyzer and Detection System.- 2.3. Energy Calibration.- 2.4. Multidetection Techniques.- 3. High-Resolution Studies of Atoms.- 3.1. Analysis of Energy-Loss Spectra.- 3.2. Argon.- 3.3. Krypton.- 3.4. Xenon.- 3.5. Equivalent-Core Model.- 4. High-Resolution Studies of Molecules.- 4.1. Nitrogen.- 4.2. Carbon Monoxide.- 4.3. The Application of the Equivalent-Core Model to Chlorine.- 4.4. Polyatomic Molecules.- 5. The Observation of Electric-Dipole-Forbidden Inner-Shell Transitions.- 5.1. Experimental Details.- 5.2. Electric-Dipole-Forbidden Inner-Shell Transitions in Atoms.- 5.3. Electric-Dipole-Forbidden Inner-Shell Transitions in N2.- 5.4. Electric-Dipole-Forbidden Inner-Shell Transitions in Other Molecules.- 6. Inner-Shell Resonances.- 6.1. Experimental Details.- 6.2. Inner-Shell Resonance in N2.- 6.3. Inner-Shell Resonance in Other Molecules.- References.- 9 Coherence Effects in Electron Emission By Atoms.- 1. General Introduction.- 2. Interference of Contributions from Different Magnetic Substates―Angular Electron Intensity Distribution.- 2.1. Introduction.- 2.2. Theory.- 2.3. Comparison with Experimental Results for Autoionization of He**(2p2) 1D.- 3. Interference of Contributions from Different States in One Atom.- 3.1. Introduction.- 3.2. Theory.- 3.3. Comparison with Experimental Results for Collisions of Li+ with He.- 4. Interference of Contributions from Direct and Indirect Processes.- 4.1. Introduction.- 4.2. Theory.- 4.3. Comparison with Experimental Results for the Process ?- + He ? He*(1snl) + ?-.- 5. Interference of Contributions from Different Distances on One Potential Curve.- 5.1. Introduction.- 5.2. Theory.- 5.3. Comparison with Experimental Data for Inner-Shell Electron-Impact Ionization of Ar L Followed by Auger Decay.- 6. Interference of Contributions from Different Atoms.- 6.1. Introduction.- 6.2. Theory.- 6.3. Comparison with Experimental Data.- References.- B: Scattering and Collision-Induced Processes.- 10 Inelastic X-Ray Scattering Including Resonance Phenomena.- 1. Introduction.- 2. Theory.- 2.1. Resonant Scattering Involving Photons and Electrons.- 2.2. Statistical Formulation of Inelastic Scattering.- 2.3. Nonrelativistic Cross Section.- 3. Nonresonant Scattering.- 4. Resonant Scattering.- 4.1. Evolution of Resonant Scattering into Fluorescence.- 4.2. Total Cross Section.- 4.3. Infrared Divergence.- 5. Relativistic Amplitude for Inelastic Scattering and Gauge Invariance.- 5.1. Relativistic Formulation.- 5.2. Gauge Invariance.- 5.3. Length versus Velocity Forms.- 6. Angular Distribution and Polarization.- 6.1. General Formalism for Inelastic Photon Scattering.- 6.2. Scattering Patterns in Dipole Approximation.- References.- 11 Rayleigh Scattering: Elastic Photon Scattering by Bound Electrons.- 1. Introduction.- 2. Physical Features of Elastic Scattering.- 2.1. The Blue Sky of John William Strutt.- 2.2. “Elastic” versus “Coherent” Scattering.- 2.3. Scattering by Free Electrons: Thomson and Compton Scattering.- 2.4. Photon Polarization Effects.- 2.5. Classical Scattering by a Bound Charge.- 2.6. An Independent-Electron Atomic Model.- 2.7. High-Energy Scattering and the Form-Factor Approximation.- 2.8. Scattering from a Compound System.- 3. Development of Theory.- 3.1. The Rayleigh Scattering Amplitude.- 3.2. Simple Atomic Scattering-Factor Theories.- 3.3. Total-Atom Elastic Scattering Amplitudes.- 4. Development of Experiment.- 4.1. Direct Measurements of d?/d?.- 4.2. The Anomalous Scattering Factors.- 5. A Comparison of Theory and Experiment.- 5.1. Differential Scattering of Low-Energy Gamma Rays.- 5.2. Small-Angle Scattering.- 6. Rayleigh-Scattering Applications.- 6.1. Solid-State Structure Studies.- 6.2. Nuclear Structure Studies.- 6.3. Observation of Delbrück Scattering.- 6.4. X-Ray Diagnostics.- 6.5. Narrow-Beam Attenuation.- 7. Further Research Topics.- References.- 12 Electron-Atom Bremsstrahlung.- 1. Introduction.- 2. Observables and Assumptions.- 3. History.- 4. Characteristic Distances and Appropriate Formulations.- 5. The Coulomb Spectrum.- 6. Screening.- 7. End Points of the Spectrum.- 8. Angular Distributions and Polarization Correlations.- 9. Comparison of Theory and Experiment.- 10. Some New Developments.- References.- 13 X-Ray and Bremsstrahlung Production in Nuclear Reactions.- 1. Introduction.- 2. Theory of Interference Experiments.- 2.1. Basic Idea.- 2.2. Survey of Atomic Collision Processes.- 2.3. Quantum-Mechanical Theory.- 2.4. Discussion.- 3. Interference Experiments.- 3.1. K-Shell Ionization in Elastic Proton Scattering Reactions.- 3.2. Bremsstrahlung Emission near Elastic Proton Resonances.- 3.3. Ionized Electron Measurements.- 3.4. Isobaric Analog Resonances.- 3.5. K-Shell Ionization by Neutrons.- 3.6. Cross-Section Measurements.- 3.7. K-Shell Ionization in Inelastic Nuclear Reactions.- 4. United-Atom X Rays.- 4.1. Theory.- 4.2. Experiments.- 4.3. Widths of United-Atom K X-Ray Lines.- 5. Conclusion.- References.- 14 Positron Production in Heavy-Ion Collisions.- 1. Introduction.- 2. Electron-Positron Excitations in Superheavy Quasimolecules.- 2.1. Time-Dependent Perturbation Theory.- 2.2. Ionization and Electron Emission.- 3. Positron Creation.- 3.1. Inclusion of Supercritically Bound States.- 3.2. Collisions with Nuclear Delay.- 4. Experimental Configurations for In-Beam Positron Spectroscopy.- 4.1. Requirements for the Detection Systems.- 4.2. The Orange-Type ? Spectrometer.- 4.3. Solenoidal Positron Transport Systems.- 5. Data Evaluation and Background Subtraction.- 6. Experimental Results and Discussion.- 6.1. First Results and Gross Features.- 6.2. Positron Spectra in Deep Inelastic Collisions.- 6.3. Peak Structure in the Positron Spectra at “Elastic” U + U and U + Cm Scattering.- 7. Summary and Outlook.- References.- 15 X-Ray Processes in Heavy-Ion Collisions.- 1. Introduction.- 2. K X Rays.- 2.1. Lighter Systems.- 2.2. Heavy Systems.- 3. MO X Rays.- 3.1. Lighter Systems.- 3.2. Heavy Systems.- 4. Other X Rays.- 5. Conclusions.- References.- Author Index.