# X-Ray Atomic Data

Description:

In astrophysics most of the X-ray emission is produced either by one of two processes. Stellar coronae, supernova remnants, galaxies and clusters of galaxies show emission features primarily produced by collisions between electrons and ions. Black holes and neutron stars produce strong high energy continuum emission by unknown processes; this emission in turn photoionizes the surrounding environment. We look through this environment and may see emission or absorption features implanted on the continuum.

Spectral models which include large numbers (thousands to even millions) of spectral features are used to interpret the X-ray spectra. Properties of the spectral features are compiled into large atomic databases to support this modeling effort. The databases require accurate and complete data, and are routinely updated with improvements from atomic theory. High energy astrophysics thus relies on the microphysics of ions and electrons to understand the macrophysics of extreme environments.