The NIST Physics Laboratory provides a number of databases on atomic properties that are available on the World Wide Web. These data are widely used for plasma modeling and other applications. We have recently added several new databases and upgraded existing ones to provide larger sets of critically evaluated atomic data along with a more powerful and user-friendly interface.
During the past year, two new databases became available. First, the Handbook of Atomic Basic Spectroscopic Data v.1.0 was designed to provide a selection of the most important and frequently used atomic spectroscopic data for the neutral and singly-ionized atoms of all elements of hydrogen through einsteinium (Z = 1-99). Wavelengths, intensities, and line classifications are given for the approximately 12,000 lines of all elements. Another database, the Spectral Data for the Chandra X-ray Observatory v.1.1, contains tables of critically compiled wavelengths, energy levels, line classifications, and transition probabilities for ionized spectra of neon (Ne V to Ne VIII), magnesium (Mg V to Mg X), silicon (Si VI to Si XII), and sulfur (S VIII to S XIV) in the 20 Å to 170 Å region. The transition probabilities were obtained mainly from recent sophisticated calculations. The data will also be useful for diagnostics of plasmas encountered in fusion energy research. The NIST Atomic Spectra Database (undergoing upgrade from v.2.0 to v.3.0) has been significantly extended and updated. The data were incorporated into the MySQL relational database management system, which provides an improved level of database operation and maintenance. A considerable amount of data has been added, including for example spectral data for highly charged ions of the iron-period elements and Cu, Kr, and Mo. There are now more than 70,000 energy levels and 100,000 spectral lines in the database. The user interface of ASD has been greatly enhanced. The search and selection options are extended and offer a variety of choices for convenient access to the desired data. Moreover, a number of parameters, such as multiplet wavelengths and A-values, are calculated on-line according to the specific request of the user. Another major development includes several graphical features, such as Java Grotrian diagram interface, Saha-LTE plasma emission plots for arbitrary temperature/density, and line identification plots.