Abstract
The new NIST Atomic Spectra Database (ASD) interactive Web site is accessible via:
http://atm.nist.gov/asd. The new version covers a much wider range of atomic and ionic transitions and energy levels than earlier versions, and all data are integrated. ASD also has a new user interface and search engine. ASD contains spectral reference data, which have been critically evaluated and compiled by NIST. Version 2.0 contains data on about 900 spectra, with about 70 000 energy levels as well as 91 000 lines ranging from about 1 Angstrom to 200 micrometers, roughly half of which have transition probabilities with estimated uncertainties. Energy level data are included for most spectra of H- Kr (Z = 1 to 36), Mo (Z = 42), plus the lower spectra of the Lanthanide rare earths (Z= 57 to 71) up to the fifth spectrum. Wavelengths of observed transitions are included for the first 99 elements in the periodic table. Classified lines with transition probabilities are included for most spectra of H - Ni (Z = 1 to 28); comprehensive wavelengths 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. Also included are NIST data published in the CRC Handbook of Chemistry and Physics, which consist of wavelengths and relative intensities for prominent lines (for which classifications are not given) of up to the first five spectra, plus selected transition probabilities for many spectra. References to the above NIST compilations and original data sources are listed in the ASD bibliography. Full search and filter capabilities are provided by the database.