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Introduction to the Atomic Spectra Database

The Atomic Spectra Database (ASD) contains data for radiative transitions and energy levels in atoms and atomic ions. Data are included for observed transitions of 99 elements and energy levels of 88 elements. ASD contains data on about 830 spectra from about 0.2 Å (Ångströms) to 1300 m, with about 92,000 energy levels and 174,000 lines, 68,000 of which have transition probabilities listed. The most current NIST-evaluated data associated with each transition are integrated under a single listing.

Energy level data are included for most spectra of H-Kr (Z=1-36), Mo (Z=42), plus up to the first five spectra of the lanthanide rare earths (Z=57-71). Classified lines with transition probabilities are included for most spectra of H-Ni (Z=1-28); output for these can be ordered by either multiplet (for a given spectrum) or wavelength. Also, prominent lines (unclassified) with wavelengths and relative intensities are included for up to the first five spectra of H-Es (Z=1-99). Some transition probabilities are listed for selected lines of Cu-Es (Z=29-99). Comprehensive wavelength lists of observed lines with relative intensities are incorporated for all spectra of Mg, Al, S, Sc, plus Be I, O II, and Ne I.

Each page of the ASD database (except the ASD home page) includes a menu bar displayed at the top of the page which can be used to navigate through the database.

The List of Spectra page provides a textual description of the contents of the database and access to the lists of Holdings for Spectral Line and Energy Level Data.

The database includes a variety of output options and search criteria.

Online: March 1999   -   Last update: May 2011