FOR IMMEDIATE RELEASE: TN-6114
July 3, 1996

Linda Joy
(301) 975-4403
linda.joy@nist.gov

NEW AND IMPROVED SPECTROSCOPIC
REFERENCE DATA VOLUME AVAILABLE FROM NIST

A new edition of a widely cited reference volume of spectroscopic data is now available from the National Institute of Standards and Technology. Atomic Transition Probabilities of Carbon, Nitrogen and Oxygen A Critical Data Compilation is a greatly expanded and improved update to tables previously published by the National Bureau of Standards (now NIST) in 1966.

Scientists in atmospheric physics, astrophysics, nuclear fusion, plasma processing and related fields will find this volume a valuable resource. Spectroscopic data are also necessary in the lighting industry, in materials processing and semiconductor production.

Every element has a unique spectral signature. Scientists use spectral data to identify and measure the abundance of elements in the sun and stars. For example, astronomers measure the spectrum radiating from a star to determine its chemical makeup. In another example, plasma modelers use large spectral data sets to characterize discharges and optimize the plasma conditions.

The new 532-page reference data book authored by Wolfgang Wiese and Jeffrey Fuhr of NIST's Atomic Physics Division contains critically evaluated atomic transition probabilities for all ions and neutral atoms of carbon, nitrogen and oxygen. The new edition contains 12,500 spectral lines, nearly 10 times as many as the previous edition. With nearly 1,000 lines each, neutral carbon, nitrogen and oxygen atoms and their singly charged ions are covered in the greatest detail.

The uncertainties of many of the new atomic transition probability data are significantly smaller than in the old volume. In many cases, the uncertainties are three to five times smaller. Typical data uncertainties are now only 10 percent, but some lines have uncertainties as high as 25 percent. For the less complex higher ions, uncertainties are usually not exceeding 3 percent.

The spectral data are presented in tables containing the latest wavelength and energy level data, pertinent spectroscopic configurations and transition probabilities, as well as related quantities, such as oscillator strengths. Allowed and forbidden transitions are tabulated separately.

The previous version of this volume has been cited widely by researchers publishing results in scientific journals. According to the Institute for Scientific Information, Atomic Transition Probabilities, Volume I was cited more than 1,200 times from 1966 to 1989. Atomic Transition Probabilities of Carbon, Nitrogen and Oxygen A Critical Data Compilation is available for $130 from the American Chemical Society, 1155 16th St., N.W., Washington, D.C. 20036, fax: (202) 872-6067, e-mail: kxw96@acs.org. Within the United States, the volume can be ordered by phoning 1-800-227-5558. Select menu options 9, 1 and 1 to be connected to a salesperson.

As a non-regulatory agency of the Commerce Department's Technology Administration, NIST promotes U.S. economic growth by working with industry to develop and apply technology, measurements and standards.

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