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Production and Decay of Atomic Inner-Shell Vacancy States Tom Gorczyca Western Michigan University

Production and Decay of Atomic Inner-Shell Vacancy States Tom Gorczyca Western Michigan University. Inner-Shell Photoabsorption: Orbital Relaxation, Spectator Auger Decay. Inner-Shell Vacancies in Atomic Ions:

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Production and Decay of Atomic Inner-Shell Vacancy States Tom Gorczyca Western Michigan University

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  1. Production and Decay of Atomic Inner-Shell Vacancy States Tom GorczycaWestern Michigan University Inner-Shell Photoabsorption: Orbital Relaxation, Spectator Auger Decay Inner-Shell Vacancies in Atomic Ions: Fluorescence vs. Auger Decay, Initial Populations, Configuration Interaction

  2. Inner-Shell Vacancy Fe XXIII + e- Fluorescence Auger Decay Inner-Shell Photoionization of Fe XXII

  3. I: Inner-Shell Photoexcitation of O Motivation: Synchrotron Measurements and Observations of (Neutral and Ionized) Oxygen Absorption Features in the Interstellar Medium

  4. Inner-Shell Vacancy:Orbital Relaxation O I (1s22s22p4) O II* (1s2s22p4) 2p - O II* 2p - O I Need Multiple Orbitals and Configurations for an Accurate Atomic Description

  5. Inner Shell Photoexcitation of O 1s Vacancy Rydberg State Participator Auger Decay Width:   n-3 → 0 Explicit Channels Included Spectator Auger Decay Width:   n0 = constant Infinite Number of Channels

  6. Mirroring Resonances Damped Fano Profiles

  7. Participator Auger Decay Spectator Auger Decay Standard (solid) vs. Optical Potential (dashed) R-matrix Theory vs. Experiment

  8. Entered into CHANDRA Database (1998) Experiment Experiment vs.R-matrix No Relaxation of Orbitals: Poor Energy Positions 1s→2p 1s→3p No Spectator Auger Decay: Unphysically Narrow Resonances Participator:   n-3 Spectator:   n0 O2(1s→π*)

  9. Experiment vs.Optical PotentialR-matrix Relaxation and Spectator Auger Decay Included 1s→2p 1s→3p O2(1s→π*)

  10. NO = 1018-1019cm-2 Intensity: I = I0 e-σN Column Density: N = ∫ n dx

  11. II: Fluorescence and Auger Decay of Inner-Shell Vacancy Ionic States Motivation: Modeling of Shocked and Photoionized Plasmas with Production of a 1s-Vacancy • Active Galactic Nuclei • X-Ray Binaries • Supernova Remnants • Intracluster Medium of Galaxy Clusters

  12. Inner-Shell Vacancy Fe XXIII + e- Fluorescence Auger Decay Inner-Shell Photoionization of Fe XXII

  13. Fe XXIII Fluorescence Yield = 0.4903 Existing Fluorescence/Auger Data Base

  14. Kaastra & Mewe (1993) Gorczyca et al. Ap.J. (2003) Comparison of Be-Like Fluorescence Results Explicit calculations for neutrals only E. J. McGuire (1969,1970,1971,1972) Explicit calculations performed for each member of the sequence using AUTOSTRUCTURE H-like Z-scaling for higher members Multiconfiguration Intermediate Coupling Single-configuration LS coupling Ratio of Configuration Averages Configuration Average of Ratios

  15. Fluorescence Yield Results

  16. Fluorescence Yield Results

  17. Fluorescence Yield Results Be-like Problematic - What about Li-Like?

  18. Kaastra and Mewe (1993) Fe XXIV Fluorescence Yield = 0.0 ! Li-Like Single Configuration:Fe XXIV (1s2s2) → 1s2 + e-only Li-Like Configuration Interaction:Fe XXIV (c11s2s2 +c21s2p2) → 1s2 + e- 84% → 1s2p + hν 16%c22≈ 0.10Fluorescence Yield = 0.16 ≠0.0 !

  19. Summary Higher-order description of autoionizing states (and their decay) is required for accurate astrophysics data: Photoabsorption of O and Fluorescence of Ions. Collaborators C. N. Kodituwakku, K. T. Korista, O. Zatsarinny, I. Dumitriu, M. F. Hasoglu Western Michigan University N. R. Badnell University of Strathclyde, Glasgow, UK B. M. McLaughlin Queens University, Belfast, UK D. W. Savin Columbia University J. Garcia, C. Mendoza, M. A. Bautista, T. R. Kallman, and P. Palmeri E. Behar and M. H. Chen Supported in part by NASA

  20. “Astrophysicists work on `Important’, `Big’ problems and think that the basic physics that they require to solve their problems has already been done, or, if it has not been done, it is easy and can be readily reproduced, as opposed to the hard problems they are working on. They have it backward. Getting the basic data is the hard part. When all the basic physics is known, pushing the `state-of-the-art’ becomes straightforward.’’ Robert L. Kurucz, Harvard-Smithsonian Center for Astrophysics Atomic and Molecular Needs for Astrophysics 3rd International Conference on Atomic and Molecular Data and Their Applications AIP Conf. Proc. 636, 2002.

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