X-RAY SPECTROSCOPY
AND ATOMIC DATA
Current Status

Collaborators

Outline

Introduction

Features of the X-Ray Band:
Highly Ionized Atoms

A New Era in X-Ray Astrophysics:
Chandra and XMM-Newton

The Difference High Spectral Resolution Makes (Capella)

Stellar Coronae:
Hot, Collisional X-Ray Sources

Coronal Steady-State Approximations

Coronal Steady-State Approximations

Stellar Coronae (cont.):
Temperatures and Abundances

Coronal Abundances (cont.)
Fe-L uncertainties most suspect

Galaxy Clusters:
Absence of the Cooling Flows

Dielectronic Recombination (DR): The weak link in the ioniz. balance

When the coronal approximation breaks down …

Beyond the Coronal Regime (cont.) Density Diagnostics

Presence of UV Field

Can we trust rates for transition
among excited levels?

Fe-L – Quick Summary

There is Life After Fe-L …

The world beyond Fe-L (e.g. Ar)

Collisional Plasmas:
Atomic Data Status

Spectroscopic Measurements in
Photoionized Plasma

1s-2p (Ka) Inner-Shell Absorption

1s-2p Inner-Shell Line Comparison

Inner-Shell Line Comparison

Need for Laboratory Experiments
Z Pinch (& Laser Plasma)

Inner-Shell Absorption (cont.)
Fe M-shell 2p-3d UTA

Fe M-shell 2p-3d UTA (cont.)

Type II AGN (cont.)
Measuring Elemental Abundances

Low-T DR of Fe-L

Photoexcitation-Autoionization

Conclusions