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Since the compilation of the Revised Multiplet Table (Moore 1945) and the Ultraviolet Multiplet Table (Moore 1950, 1952, 1962), herein denoted as the RMT and the UMT, respectively, significant progress has been made in the analysis of atomic spectra. Unfortunately, the results are scattered in the literature. Although extensive bibliographies of atomic spectroscopy papers have been published, it is often difficult to determine which studies are the most suitable for one's purposes without an extensive literature search.

The need to use supplementary sources has increased in recent years. The RMT, in particular, does not contain the spectra of certain ions which were discovered in stellar spectra subsequent to the publication of these tables (e.g., Er III, Pt II, Hg II). Studies of the visible spectra of peculiar A stars (e.g., Adelman 1974) have illustrated the necessity of using sources other than the RMT for the identification of certain lines of common ions such as Cr II and Co II. In addition, studies of stellar spectra in the region lambdalambda910-3000, and the recent development of fully line-blanketed model atmospheres (Fowler 1974; Kurucz 1974) have illustrated the need for more complete spectroscopic data in the ultraviolet. Snijders and Lamers (1974) have shown the eflects of ultraviolet line blocking on the results of non-LTE calculations of Mg II lines. Leckrone, Fowler, and Adelman (1974) have performed simple numerical experiments with fully line-blanketed model atmospheres to qualitatively reproduce the flux distributions of peculiar A stars (Leckrone 1973) and the nature of their photometric variations (Molnar 1973a, b; Leekrone 1974). Investigations of this sort rely heavily upon the availability of the pertinent atomic data.

Some work has been done to ameliorate this situation. New multiplet tables for selected light ions have been completed (Moore 1965, 1967, 1970, 1971, 1972) while others are in preparation. Kelly and Palumbo (1973) have compiled a comprehensive finding list for the first 36 elements in the vacuum ultraviolet below 2000 Å. In addition, extensive bibliographies of atomic spectra are available: Moore (1968, 1969), Hagan and Martin (1972), and Edlèn (1973).

To facilitate the compilation of atomic data necessary for the above-mentioned types of astrophysical research, we have assembled in Table I a selected list of the best wavelength tables to supplement those contained in the UMT, the RMT, and Kelly and Palumbo (1973) for the first four spectra of all elements. For C, N, O, and Al some higher spectra are also included. The wavelength region covered is lambdalambda911-8205, i.e., the Lyman to the Paschen limit. Below lambda911, interstellar Lyman absorption prevents the observation of the spectra of all but the closest stars while longward of lambda8205, high-resolution astronomical observations are still scarce. Near 2000 Å the data may be incomplete due in part to the poor overlap in vacuum and air laboratory measurements.

To keep the list manageable, we attempted to find for each spectrum as few references as possible which give a complete listing of all reliable wavelength tables available, together with a thorough analysis of the speetnim and classifications of the listed lines. In adldition, we includled only papers which are generally available. Hence, very few dissertations and "in preparation" papers are listed. For each publication used, we give in angstroms the wavelength range covered and note the type of paper: NMT = multiplet table, A = analysis, RA = revised analysis, EA = extension of analysis, W = line list, TC = temperature classification, and CL = classified lines. We included some publications which were UMT and/or RMT sources when they contain additional lines which might under certain cirucmstances be important. These sources are noted as such. In all cases, we recommend that the user examine the papers listed to ascertain their quality.

If we compare the sources listed in Table I with those used for the multiplet tables, the progress made since their compilation is clearly illustrated. For the spectra of the first 20 elements both in the UV and the visible only 20% of the spectra have not been revised or extended, while about 10% of the spectra listed are completely new. Only seven spectra of these first 20 elements are still unknown (B IV, F IV, Na IV, the visible spectrum of Al IV, K IV, Ca IV) but work on the majority of them is in progress. For the heavier elements the situation is in principle the same; however, for the rare earths the rapid expansion of our knowledge should be especially noted.

We gratefully acknowledge the assistance of Dr. Lucy Hagan of the National Bureau of Standards and the NASA Goddard Space Flight Center Library.

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